I made another pair of pants to purse. I love making these. I do mine just a little different. It helps hide the hips in the purse giving a straighter line down the sides.
I usually make all mine out of kids pants. Having 2 constantly growing kids helps with supplies. When supplies are limited I hit garage sales and thrift stores.
1. Rip out the inner pant seam. Then rip out the seam in front of pants up to the zipper. In the back I rip it to about 1.5 - 2 inches from the waistband.
2. Pin the waistband so it's nice and even. Then play around with legs till you get the length you want. Then pin those.
3. When you are all pinned cut off the excess. Leave room at the bottom so you can square of the bottom of the bag. You'll see later.
4. Sit the extra legs aside and start sewing your seams. Flip the purse inside out and sew the bottom closed. Then you need to square off the corners.
5. The liner. I lay the already sewn bag down on the liner and draw out the pattern for the liner.
6. Sew up the liner and set it aside. Don't forget to square off.
7. Now the strap. Take those extra pants remnants and separate all the seams. Play around till you have the length you want then pin and sew.
8. Now it is the end, assembling. I prefer to put the bag all together and sew it closed from the outside. Working with that much denim makes my machine crazy so I try to make it easier on her. You can always leave the seam open at the bottom of the liner then flip and stitch if you prefer that look. I usually don't like the way mine turn out doing that. Plus this way is easier.