January 17, 2024

DIY Messenger Sling Bag Sewing Tutorial

The messenger sling bag is the perfect handbag for hands free shopping and big enough for all your essentials.

I created this messenger sling bag to carry as a handbag while on my vacation. This messenger bag is the perfect size for all my necessities I carry in a purse plus extra room to stash items I bought along the way. I also sewed a matching wristlet purse and small zipper pouch for my cash and cards. I loved how this messenger sling bag turned out and wanted to share the steps for you to create your own!

Here are the instructions on how to sew a messenger sling bag:

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***You can find the ad-free, printable PDF version of this sewing tutorial available for purchase in my Etsy shop HERE. Includes 20 pages of step-by-step instructions with pictures. Print a copy to keep next to your sewing machine for easy reference.***

Messenger sling bag supplies needed:

Cotton fabric – one yard for outer fabric and straps – my favorite fabric shop
Cotton fabric – one yard for lining fabric
Fusible interfacing – Pellon 911FF Fusible Interfac ing
Cu tting mat
Rota ry cutter
Clear ruler
T wo 1.5 inch rectangle rings
O ne 1.5 inch rectangle slide
One ma gnetic snap
Seam ripper
Matching thread
S ewing scissors
Sewing gauge
Marking pencil
S ewing machine

Measure and cut the fabric

Floral and dots fabric for messenger bag

Using your cut ting mat, clear ruler, and rotary cutter, cut two pieces of the outer fabric and two pieces of the lining fabric 11 inches by 11 inches for the body of the messenger sling bag.

Cut one piece of the outer fabric and one piece of the lining fabric 10.75 inches by 11 inches for the closing flap.

The sides and bottom of the messenger sling bag will be one continuous strip (or two strips sewn together, if you don’t have one continuous strip) – cut one piece of the outer fabric and one piece of the lining fabric 6 inches by 33 inches. Basically, you’re adding the length of the sides and the bottom together to get the length of the strip.

For the long strap, cut one piece of outer fabric 6 inches by 48 inches (can make longer if needed). For the short straps, cut two pieces of the outer fabric 6 inches by 3 inches.

Keep track of your sewing projects, like this one, with a sewing planner. This sewing planner is specifically designed for non-clothing sewing projects and helps you stay organized – fabric used, measurements, hardware used, notes, etc. Also included are pages such as sewing tips and fabric shops. Get your sewing planner HERE.

Sewing project planner to help keep your sewing projects organized.

Attach the fusible interfacing

I use Pellon 911FF Fusible Interfacing for all of my handbag and accessories sewing projects. You will need to cut interfacing for ALL the cut fabric pieces. Follow the package instructions for attaching the fusible interfacing to the messenger sling bag.

Interfacing 1/2 inch from edge of long strap

NOTE: Cut the interfacing for the long strap about 1/2 inch shorter in length on each end for hemming (see above picture).

Add inside pockets (optional)

At this point, you have the option of adding pockets to the lining fabric pieces if you want pockets on the inside of your messenger bag. To add a zipper pocket, follow these instructions on how to add a zipper pocket. For slip pockets, follow these instructions on how to add slip pockets to a bag.

Make the messenger sling bag long strap

The finished strap will be 1.5-inches wide.

RULE OF THUMB: Decide how wide you would like your strap to be and then multiply by 4 and that will be how wide to cut your fabric. For this bag, 1.5 inches wide means I need to cut the fabric 6 inches wide.

Fold the strap in half lengthwise and press along the fold.

Open back up and fold the outside edge to the center and press.

Turn the strap around and fold the other outside edge to the center and press.

Fold in half again and press.

Hemmed end of messenger sling bag long strap

Open back up and fold each short end in about 1/2-inch and press. Fold the strap together again and press. Hemming the strap gives it a finished look.

Sew the strap along the folded edges.

Make the messenger bag short straps

Fold each strap in half lengthwise (3-inch sides together) and press along the fold.

Open back up and fold the outside edge to the center and press.

Fold other side of short strap to center

Turn the strap around and fold the other outside edge to the center and press.

Fold short straps of messenger sling bag in half again

Fold in half again and press. You will not be hemming the short straps.

Repeat with the other short strap.

Sew each strap along the folded edges.

Round the bottom corners of the messenger bag

Round the corners of the messenger sling bag

Line up the bottom right corner of one of the outer fabric pieces with the corner of the cutting mat. Find a lid or a plate to trace with your marking pencil – I use an old yogurt container lid. You’ll want to be about 2 inches away from the corner on both sides. Trace with your marking pencil. Use your sewing scissor s and cut along the pencil line.

Line up the left bottom corner, trace, and cut.

Repeat with the lining fabric bottom corners and the flap closure bottom corners.

Rounded corners of the messenger sling bag

Your rounded corners should look like the above picture.

Add magnetic snap to messenger sling bag flap cover

The magne tic snap has four parts – male, female, and two washers.

You’re going to attach the male magnetic snap to the lining side of the flap cover.

Place magnetic snap washer on flap lining fabric piece

Figure out where you would like the magnetic snap to be and place one of the washers there.

Mark the slots in washer with fabric pencil

Mark the washer slots on the f abric with a marking pencil. Cut the slits with your seam ripper (cut just a bit smaller than your pencil mark. You don’t want the slits too big).

Push the prongs on the male magn etic snap through the slits you just made.

Place the washer on the back of the snap as shown in the above picture.

Hold down the washer and fold one prong towards the center of the snap. I use scissors or something sturdy to push down on the prong. Repeat with the other prong.

The female magnetic snap will be added after the messenger sling bag is sewn together.

Sew the messenger bag flap cover

Messenger bag flap cover right sides together

Place the outer fabric piece of the flap cover on top of the lining piece, right sides together. Pin in place.

Sewing together messenger bag flap cover

Starting at the top right, sew around to the top left.

Make little triangle cuts around the bottom curves using your sewing scissors.

Turn right side out and press. Top stitch around starting at the top right and finishing at the top left to give it a finished look. Note: I decided to add the top stitching after I finished the bag.

Attach the cover flap

Attach flap cover to messenger sling bag

Place the cover flap on top of the back outer fabric piece of the messenger sling bag with the lining side facing up. Pin at the top to hold in place.

Baste flap cover to back fabric piece of the bag

Baste the cover flap to the outer fabric piece.

Sew the messenger sling bag together

Pin bottom fabric strip to lining fabric

Attach bottom fabric strip to lining fabric

Start with the lining fab ric. Pin the lining bottom fabric strip to one of the lining fabric pieces as shown in the above pictures.

Sew all around starting at the top right of the bag.

Repeat with the other lining fabric piece. The trick to pinning the curves is to place the pins close together, eliminating gaps.

Cut little triangles around the curves.

NOTE: Be sure to watch underneath when sewing – you don’t want to sew any folds!

Repeat the whole process with the outer fabric pieces and outer bottom fabric strip.

The above picture shows what your messenger sling bag should look like at this point.

Attach the short straps

Slide the strap through the rectangle ring and fold over

Slide one short strap through one of the r ectangle rings and fold over.

Baste the short straps to the sides of the outer bag

Baste the short strap to the side of the outer bag as shown in the above picture.

Baste the other short strap with rectangle ring to the other side of the outer bag.

Add the magnetic snap to outer bag

Turn the outer bag right side out and press the seams.

Fold the cover flap over and mark where the female snap should go with your marking pencil.

Place washer over dot and mark the slots

Place the washer over the dot and mark the slots in the washer. Follow the same steps to attach the female magnetic snap.

Turn the outer bag back to wrong side out.

Time to sew the bag together

Place lining bag inside outer bag right sides together

Turn the lining bag right side out and place inside the outer bag. The right side of the fabrics should be facing each other.

Line up the seams and pin in place, leaving an opening for turning

Sew around the top, leaving an opening for turning

Line up the seams and pin in place. Be sure the cover flap and the short straps are between the bags. Sew all around, leaving an opening in the front for turning. Sew over the short straps a couple times for extra durability.

Turn right side out. Push the lining inside the bag. Press.

Top stitch around the top of the messenger sling bag

Top stitch around the top giving the bag a finished look and closing the opening for turning.

Attach the long adjustable strap

Slide the strap through the rectangle slide

The r ectangle slide is used to make the strap adjustable. Slip one end of the long strap through the slide and fold over.

Sew to attach the strap. I start in the middle and go backwards then forwards then back to the middle. This keeps the strap lined up and prevents it from moving around. (I sew two lines for extra durability).

Slide other end of long strap through rectangle ring

With the stitching facing up, slide the other end of the strap through the rectangle ring to the left when looking at the back of the bag.

End of strap all the way through rectangle slide

Then slide it through the rectangle slide. The stitching should be hidden under the strap.

Now take the end and slide it through the other rectangle ring as shown in the above picture. Be sure the strap isn’t twisted.

Sew the long strap to the rectangle ring

Fold the strap over the ring. Sew two lines to attach the strap, starting in the middle as done previously.

Top stitch along the seams of messenger sling bag

At this point, you can choose to add top stitching around the sides and bottom seams of the messenger bag. The top stitching helps the bag keep its shape.