I see this many times.Layered.Is there any rules how you should layer your frags?Any does and donts?Like what kinda frags are known to work well whit others and what not?And i read somewhere that you can ad an natural cent to the fragrance(like vanilla).And what does exactly mean natural cent?Is it like vanilla oil etc.that you can get from body shop etc?.And how do you layer them.Do you put first the oil and then frag.Or how?Nad do you test in paper first or your hand?

Help the newbie out.

Thanks.