Marion's point about stamina and patience is very true. You may busk for a while and not get any tips then you may get a lot of tips in a few seconds. Some places in the UK require a licence but most don't. You can call the local authority before and find out if you need a licence or not. Most places it's ok to turn up and do it. If you do get asked to move on (this has happened to me when I've been on private property such as shopping centres) then be polite and ask them where buskers normally go in their town/city.

Its good to have a wide range of songs/tunes, happy songs and popular songs go down really well. We make more when the sun is shining. Busking is a good way to get over nerves, at first you may be nervous about singing on the street but give it a go it's fun! 99% of the people are nice ignore the few negative comments you may get.

Smile and dress smartly. How you present yourself makes a difference. Some people dress up to go with the act I think that's a cool idea. We have been booked to play paid gigs when people have seen us busking, you are your own best advertisement!

If you are singing take a bottle of water it's thirsty work. Seamus is right to say PROJECT. I put as much energy as possible into the performance leaving enough left so I can keep going comfortabley for the lengh of the show (from 1 hour to 3 hours). Build your stamina up over time.

If you are playing a stringed instrument pack some spare strings.

If you are doing it often and walking a lot it helps hugely to get a trolley. The trolley saves my stamina and muscles for playing!!

The most important thing is to enjoy it and have fun. Good luck!