What product will give me the most natural tan?

Good ol’ Sunlight with some UV protection.

As a Greek who tans easily just being out in the sun I don’t have any first-person advice to give you on tanning creams. However, my best friend who is very pale used Jergens Natural Glow lotion. She didn’t have any complaints about it that I know of. I don’t think it’s too expensive either; $7–10 I would guess.

The sun. It is free, too.

About 1.98892 × 10^30 kilograms of three quarters hydrogen and one quarter helium will do the trick nicely. Make certain that you don’t get any closer than about 93 million miles to your concoction.

Nivea Glow bronzing lotion works. You can find that in the drugstore.

Old Sol himself. Barring that, a sun lamp.