Those squares are great, @MyrtleLion . So varied and interesting.
Woolly Hugs blankets made from squares often have a border, but don't have to. Would you be OK with picking up stitches to make one? They can stop the edges from curling.
Debbie Abrahams, who designs many blankets made from squares, recommends this blocking method:
Materials
Pins. You can use blocking pins but I use mapping pins.
Something to pin the squares to - I use blocking mats (like small children's play mats) but some people just use the carpet
Spray bottle
Method
Pin the square (or whole blanket) to the measurements you want it to be. Pin the blanket face down, unless if has things like bobbles which you don't want to squash. Otherwise, face up.
Spray the knitting with water and leave to dry. I saturate my knitting but you don't have to. Sometimes I use a tea towel to press the water into the knitting instead.
If you don't have pins or carpet, you can just put the blanket on a flat surface, smooth it out, and spray it. If you don't have a spray bottle, soak the blanket in a bowl of water for a few minutes and then get a lot of the water out by spreading it flat on a towel, then roll up the towel and stand on it a few times.
Blocking will be less effective on acrylic yarn than on wool.