it takes time if you want to do it right... i go to a tanning saloon 3-4 days a week, and I use an SPF-4 deep tanning lotion in the beds.. Im in the bed for 15-18 minutes.. when I first started, I had to do 5-6 minutes..
when i lay out in the sun, its only for 15-25 minutes wiht the same lotion.. I'm tan now, but it took at least a month of this routine to build it up...
just dont fall into the "if I go a little bit longer in the sun, i will get tanner" because then you just get burned... go out until you feel like you might be starting to burn, then go back inside..
ALSO, you have to keep your skin moisturized as well, not just when tanning, but throughout your day..