Scared of the Potty

Lilly

My son is 2.5 and we have been working on potty training but he is terrified of the potty. We got him a small one that flushes and he does okay with it but won't sit on it without a diaper and pants on. I know he will be ready when he's ready but we've been working on just sitting on the potty for w few months and it's not getting better. Any tips to encourage him to sit without a diaper?