I always used to wear a pair of blue PRIMARK chinos and a white cheap shirt. With no tie in one establishment and a tie in another.
Reason:
1. it was cheap, trousers were 4 quid a pair and shirts 5 quid.
2. you didn't need to think in the morning.
3. Trial lessons the punter has an image of what a pilot looks like. If you don't fit that image they get nervous and you have sod all chance of selling a PPL afterwards.
4. Parents of kids spending alot of money like to see the image and like to think that the money is well spent.
5. On a hot day it was by far the most comfy thing to wear.
6. Makes you different from the student so security types seem to treat you different.
7. Your a sales person. You have to fit in with what joe bloggs thinks to extract the money out of them.
Once you have started teaching them it dosn't really make a difference. You are on the next stage of the instructor student relationship.
Personally i would wear the same stuff even if it wasn't required purely because of the sales side of things
MJ