Wearing clothes which make you look like an instructor (blue trousers and a white shirt, for example) can mean you can pretend you're a training flight and get a discount on landing fees. I've not tried it, but apparently it works at Wolverhampton! I usually wear somthing that I don't mind getting oil and grass over and won't burst into flames if there's a cockpit fire. I suppose leather gloves would be useful here, but I've never worn them.