Tanning advice? 10 points for the best answer!?

So, I started the summer off with basically NO tan... Everyday for about a week I have spent a couple of hours outside, with Hawaiian Tropic Tanning Lotion SPF 8. I have gotten noticeably darker, but nothing MAJOR. . . I'm now interested in the use of tanning oil. When is a good time to start this? Please share any info!