Insert a zipper
Take the third strip, fold it along in half to define the middle and cut along the fold line. On the sewing machine, install the zipper foot. Or set the needle in the side position so that it does not fall into the zipper itself when you start sewing! (It is not necessary to have a special zipper foot, you can do this step without it too.) Pin one half of the denim strip with the pins facing down to the right side of the zipper and sew them as close to the zippers as possible. Sew the strip to the other side of the zipper, but not with the front side, but with the seamy side down,so that the two halves contrast with each other. Fold the fabric over the teeth on both sides of the zipper and attach to the wrong side.
Sew the side parts
Fold a strip with a zipper and a double strip with the front sides and stitch along the short side on both sides to form a closed piece. Tighten the allowances. Sew the side panels to the front part
Fold the front detail and the zip-up strip with the front sides together. The middle of the zipper should coincide with the middle of the front of the backpack. Fasten all the pins, straightening the fabric on the bends. Carefully stitch the details. Attach the allowances using black thread (or choose another color that suits you).
Make a loop for the handle
Cut two 10.5 by 7 cm rectangles from the same fabric that you used for the front pocket, and sew them together on the short side. Now straighten the seam, fold the fabric in half along the inside out and sew it together. You should have a long tube of fabric. Secure the safety pin on one end of the tube and carefully turn it out facing out. Bend both ends, aligning them in the middle with the sides, and press all as shown in the picture. Sew the handle to the top of the front side of the rear part.
Sew the straps
Cut out a square 11 by 11 cm from denim. Use a ruler to draw a line from one corner to the opposite and cut a square on it. Put one of the straps is 28 cm long at a right angle to the long side of the triangle and fold it in half around the strap as shown in the photo. Leave a small piece of webbing sticking out of the triangle and attach the fabric to the webbing. Turn the triangle and the webbing face out and sew the corner. For greater strength, make a square seam through the fabric and the strap tip that you left sticking out of the triangle. Do the same with the other strap and triangle, but use the fabric with the wrong side out. Place the triangles at the same height from the bottom edge back of the backpack and sew them.
Attach belt adjusters
Cut two more pieces of straps 8 cm long and burn the edges with a match or a lighter so that they are not frayed. Pass the piece of the strap through the adjuster and back Attach the end.The regulator should be attached to the end of the strap in a small loop. Attach a short strap to one end of a long (47.5 cm) shoulder strap, as shown in the photo. To understand how this will all look together in the long run, look at the first photo. (If you do not have ready-made straps, and you want to make them from scratch, cut two 47.5 cm of fabric 4 and sew them into long tubes, and then turn them outward, as in case with a handle).
Make an inner key pocket
Cut out a rectangle of 24.5 by 9.5 cm from denim. Twist one of the short ends twice and sew. Fold the rectangle with its front inward. Sew along the sides. Turn the pocket face out and make two small cuts on each side so that the seams that were inside lie flat. Wrap the small shreds that came out when you made the cuts and stitch the pocket in a circle with a contrast thread.
Minor improvements before final build
Put the webbing face up on the back of the backpack on either side of the top handle and sew them. . Check the second photo and stitch them. The third photo shows how it should look when the backpack is fully ready. The key pocket should be located near the upper edge of the backrest.
Sew the details of the backpack together
Find the middle of the upper and lower edges of the back and slats with a zipper. First, combine them and fasten with pins. Continue to straighten the fabric and fasten the back and side part around the edge. Carefully line the parts in a circle. Turn the bag with the front side out and make sure that you are satisfied.If everything looks good, make a zigzag stitch along the first seam inside, so that the fabric does not crumble. Stitch the upper edge again, where the webbing begins, since this is the main load.
Cut a small square of 4 by 4 cm leather. Fold it in half and round the corners with scissors. Mark two parallel lines along the diagonal on the back of the fabric, and then carefully cut through them. Place the square on the front side of the backpack at an equal distance from the top and side edges and pin it with pins. Gently sew the part with a straight seam in a circle.
Everything is ready!
Connect the half of the straps, passing the lower short straps through the adjusters. With this done, fold the short straps and stitch the two pieces so that they do not slip out of the adjuster.Zip up and see the end result.