I know a lot of people are suggesting Mystic Tan, but I have NEVER seen a girl that has had it done that did not look orange or streaky. MAYBE they were moving or did something wrong, but it never looked right. Especially inbetween their toes and fingers.
Jergens lotion is great, and Aveda has an amazing product called "Sun Source". Its like $16.50 a bottle (I work at a spa that sells aveda) but it is really moisturizing and it doesn't rub off on clothes, it absorbs well, it doesn't smell funny, and it isn't streaky. I absolutely loved it when I tried it. And a little goes a long way so the bottle lasts a while....

Regardless...exfoliating helps a tan look better and more even.