I found a pattern for a crochet bag the body of which was made from a singular rectangular piece of crochet here. I wanted to give it a go but had got bored of crochet so decided to try a knitted version. To work out the sizes I tried folding a piece of paper as per the instructions and then scaled it up to a size I was happy with. Feeling a bit brave I decided to try to make it stripey and see if the stripes would match up when it was folded. I think it was beginners luck! I knit a handle and attached it. I'm very pleased with the result. The only problem with it is the edges keep curling over, hopefully a quick pressing will rectify that!