One thing I'm always on the look out for is good shaped plastic bowls to use as moulds. I have a large green one and I make my best selling pots out of it.
Over and over again I painstakingly lined it with cling film so that the clay wouldn't stick to it. As I worked on it the clay would move around, the cling film would crease and sometimes rip and quite frankly it was a nightmare. But all this is history now! The new word is Vaseline or petroleum jelly.
You don't need much, just be sure you don't miss any patches and - Bob's your uncle - as we English say.
When leather hard put your hand inside, tip it over and lift the mould off. The result - a lovely smooth pot - a bit sticky but the kiln will deal with that.
Just before I go I have a quick tip to end this posting. When using a tool or a stamp to make patterns in clay you usually find that as you lift them off, the clay lifts also and stretches and distorts the pattern. Try giving the stamps a light spray of WD40. You can pattern the clay repeatedly without any trouble at all.
Happy potting folks.