I just did it like a pillowcase (with a zipper)...plain and simple. I'm pretty sure it's a size 75 universal needle that's on there now and I remember thinking that I needed to use polyester thread instead of cotton but I've been doing a lot of back and forth lately so it's possible that I forgot to switch it. For peed-on diapers, it's fine and maybe that's all wet bags are meant for. After I dunk and swish a poopy diaper, I have to wrap it in something before I put it in the bag and even then, after a couple of hours, the whole bag will be soaked...not just around the seams but the whole outside of the bag. My SIL has a giant garbage-bag sized pail liner that she actually puts in her diaper pail (imagine that!) and she tosses the soaked diapers in there after dunking or spraying them with no problems. She can pull the pail liner out and carry it to the laundry room without it dripping and the inside of the pail is still dry. But hers feels a lot thicker than my PUL as does the hand-me-down wetbag I got.
With my older kids, I had gotten two 3XL men's sweaters from Goodwill, heavily felted them, and made them into hanging bags. They were awesome. I may wind up doing that again. I'm having trouble getting the diapers good and clean in my front-loader so I'm trying to swish them and get them good and wet before I put them in the washer to trick it and I'm also thinking of getting a sprayer so I need SOMETHING that's really good and waterproof to keep in the bathroom. I guess I could just use a plastic diaper pail but those stink and have to be scrubbed all the time (hence the desire for pail liners!)
Barbara - Unexpectedly back after a long hiatus...anxiously awaiting #6!