A thread for idiot ex-pats returning for the game

Not wanting to get in the way of pub met ups and ticket distribution, I thought I would start a thread for dumb ex-pats who have been away too long, and are now challenged when it comes to living in London - Please place your questions in this thread, and may be the good ship BBS will help us:

Travel -
It seems a one day off peak 6 zone travel card would be best for getting to the game from Bromley South (or East Croydon).
Q1. Where do you buy these tickets, and can you buy them on the day at the station?
Q2. Do they take good old cash, or is this strictly a machine taking a credit card?

Tipping -
Q1. Is the going rate still 10%, or has it gone more the way of America and is now 15%?
Q2. How about cabs? if the fair is 9 pounds, do you give them a tenner and say keep the change... or as question above, is this now all done with credit cards?

Driving -
Q1. When filling up with petrol, do you still pump first, then go in a pay for it, of is this all done at the pump now?
Q2. I guess you can't still turn left on a red light if all is clear? (Turning left on red is OK in the US).

Dress code -
Q1. Will I be OK wearing plaid trousers, a ten gallon stetson hat and having a Nikon around my neck?

(P.S. The last one is a joke)