The first two part tutorial is by Izzy MEIMsaab on youtube, part one shows you have to make the bag:
The second part shows you how to line the bag:
The next youtube tutorial is from Threadbanger and I only took the flap part as inspiration:
I also have added an inner slip pocket to mine. You can easily add your own with machine sewing. Or you can sew the entire bag by hand like I did before I was given my mother's Necchi Supernova. The first tutorial, Izzy MEIMsaab's two part denim bag tutorial will show you how to cut, sew and line a pair of denim jeans into the bag itself. So I won't cover that, she shows you how to 'box' the corners to give the bag depth, and how to make and hand stitch the lining into the bag, but I will show you how to make the strap and flap, I line my flap and top stitch it as well.
You have to skip one area, the big bulky seam, and do that by hand if you desire. If possible I will machine sew the strap to the bag, and then pin the flap into the bag, check it for length and then sew it onto the bag when I sew the lining in.
A note on jeans to use, I like to use Junior sizes, my general rule of thumb is to measure the waist of the jeans against my forearm, if they are longer then the length of 14"-15" (from the crook of my elbow to the tip of my middle finger) they usually get put back on the rack, unless they are spectacular. You have to consider you're making a pair of jeans into a purse and don't need it to be diaper bag sized, so finding a cool pair of Junior sized jeans at the local thrift store is always exciting for me.
First photo up is the sewn bottom, this is just like tutorial I linked you to by Izzy MEIMsaab, you just sew it, AFTER you've done the first steps of cutting out the bag from the jeans, and sewing the front seam and back crotch seams evening them out.
Then you stitch the lining down to the boxed corners of the denim bag:
Then you want to make the strap, you can do it like IzzayMEIMsaab does or, if want a cross body or shoulder strap you can make it like I've done here. You cut out the strap pieces from the one leg of the pants. I usually try for 6 1/2" wide and try to end up with a 44" finished strap so I can easily slip it between the jeans and the lining and sew it on to secure it. After cutting your two pieces, you then sew the two long pieces together, right sides together, and then trim the seam.
Then you fold the edges towards the middle and iron it down.
Then fold the two folds to towards one another making a thinner, stronger strap, iron and proceed to top stitching You'll want to do both sides.
This you top stitch down the sides, to the middle seam, where you'll have to back stitch and end the seam, and continue after the big folded bulgy seam and the middle of the strap, starting with back stitching. Using the second leg, cut out a flap piece. I like to have the smaller thin side seam run down the middle of the flap. Measure it to the length you want and make sure you go at least 4" or 5" longer then you think you need, and then cut a lining piece to match. Sew down the three sides that will be seen, no need or use to sew the part that goes in the back of the purse. This makes it easy to turn inside out too.
Then turn right side out when you're done and top stitch. It will look somewhat like this:
Now you have your strap made you can sew it on the purse by hand or use your machine and back stitch it a few times, for added strength. Next once you have your flap lined and the lining finished, it's time to pin down everything together.
You need to put the flap in between the lining as shown above and the raw denim of the jeans part, sandwich it in between these two layers, and pin, making sure you adjust it so that you have it fall onto the front of the purse where you need it to land. Also at this point make sure you like the drape of it, if you just slap it in there it will most likely need redoing, so take care on this step and adjust it to your liking.
Hand stitch this as Izzy MEIMsaab shows in part two of her tutorials on the front area, and on the back you need to do a running stitch, I like to roll up a piece of denim and use it to push the needle through the thick layers. This part takes about 45 minutes if you take your time and then you will have your finished purse! Hope you enjoyed the alterations I have added to my style of these recycled denim purses. I hope you find fun ways to embellish your purses, here's a few of my finished examples. You can crochet corkscrew fringe, add buttons, paint, or even Bedazzle the flaps on your denim purses, but the most important part is to enjoy it. Here's a few I've made: