Step 1: General overview of minor disasters.
I cut down my bottle to the size that I wanted. I tried to melt down the edge of the bottle, as in high quality cups from recycled water bottles by Lftndbt, however, I wanted to cut my bottle at a certain spot, and the way the bottle is angled it just wanted to melt the whole top 1/2 inch over. So, I just cut it off. (It's a good idea, though!) This did leave me at a neat spot to punch holes in with a big carpet needle, so that's what I did. (Hint- use a thimble.)
This is where I should have known better. I knew that denim was too heavy of a fabric for this project, but I wanted to use it anyway because it added another layer of recycling. I also wanted to do the bleach pen thing, Easy T-Shirt Sketching (By Goosezilla) and I thought that denim would work well for that. And it did! Amazing! I thought I was on a roll, now. From this point onward it gets messy. I don't know if you want to see all of the pictures that I took for this. I will try and just give a brief overview of the mishaps that followed.
So, I had to cut the jeans and re-sew them, because they were too wide to fit the top of the bottle. (Which was expected, really.) Then I hemmed the bottom using this pretty green ribbon that I had, to try and make it a thinner hem. Then I made a channel for the drawstring at the top, but because the denim was too thick, it didn't want to "draw" together very well. So I thought, well, I can make a channel out of this pink ribbon that I have, and pin fray the top and maybe it will still look alright. This is after, by the way, I realize that I have cut the denim for the top too long, so it looks stupid, and hemmed it already. :) So, I make a new channel with the pink ribbon, and I pin fray the edge,(Ripped a hole in my jeans I was wearing while I was pin fraying it, though. A small hole, but still.) and I think, this doesn't look too bad... then I realize that the top is still too long, and it still looks dumb. OK, so I take my bottom hem apart, cutting the very edge off of the hem, so that maybe I can save some work, leaving the ribbon in place so I can use it to cover the edge of the plastic bottle on the inside. Then I figure out that the other side of the ribbon is caught in the top seam, and I still need to cut the main part of the purse off some more because it's still too long anyway. Then I accidentally stab myself with the seam ripper, and bleed all over. Then, I decide it's time to go to bed and try again tomorrow.
The next day I take the green ribbon totally off, wash it and re-iron it. I re-hemmed the bottom, and decided to pin-fray it also, just like the top. This I can live with. I start looking for the strong black carpet thread that "I know I have around here somewhere..," But I can't find it. I can only find a dark green. I decide that I will just use this other black thread that I have, it says extra strong on it, and who am I to argue anyway, I just want to be done. So, I start sewing on the top of my purse. In the middle, I quit and go to bed. The next day, I forget exactly how the stitch I was doing went. Finally figure it out. Have to adjust stitches, because there is a little too much fabric. Fabric puckers. Figure out in the middle of all this that the neck of the denim part of the purse is too small to fold down over the purse all the way so I can see what I am doing. I finally finish sewing it on. I also decide that there is no way I am going to try and sew the ribbon down over the top of the bottle part. So I get out this fabric glue. I think maybe it will stick to the stitches that I made in the plastic. It doesn't. Then I try this other glue I suddenly remember I have, and so far, I think it's working OK. So, then I'm done. But the program I was trying to use to crop my pictures, the format doesn't transfer to Instructables correctly, wrong picture file or something. So I guess you guys have to put up with un-cropped pictures until I can figure out a way to do it without permanently altering my picture files. The end. Now, was that a laugh-and-a-half, or what? Like a friend of mine said, it will make a good story in about a week. I think I'll just send them all here to read this Instructable. :)