Mystic Tan Las Vegas

I get a Mystic Tan next Monday, as a test for my wedding. (Due to budget constraints, I can not go to the airbrush tanning place) when my fiance (then b / f) and I went to Las Vegas in January, I also used Mystic tan, while I that was required to do so (exfoliate, etc.) kept the spray tan over the length and they told me, but I did not even see the difference ... all. I was always the same pale color as before I had the spray tan. However, I give another chance, because I am determined to find an affordable way to tan! So do any of you have advice on how to more effectively mystic tan? (The formula uses this place is one without a tan, and should be left in place for 3-8 hours)

I really do not want to UV-tan because skin cancer runs in my family and I have tried tanning from the hardware store but I do things ...

when you go to the right place to let them know it didn't work the last time even if you have taken all necessary precautions
im white and cannot Tan UV due to skin cancer as
I'm learning to love my pale fine, but I understand where you come from
just let them know that didn't work and see what they can do (:
it may be useful