Better results

So after these attempts I learnt a lot. I knew that I had to get a new mould and that the carrier bag idea was a good one but that it was still hard to get the plaster out afterwards. I think part of the problem was on the previous attempt it had been in a pop bottle and had a slight ridge round it which made it hard to get the plaster out and that's why I had to cut it. So to solve this I got a new pot/mould thats walls were staright but at a slight angle and then put a little bit of washing up liquid in before the carrier bag went in so it would be easier to get it out. This worked perfectly and I realised Plaster of Paris sets really quickly: