Hi and welcome to the forum!
Please share a bit more information about what you would like to accomplish using pheromones. What situations are you thinking of? Work? School? Friends? Family? Romance? What kinds of effects would you like to see?
Instant Openess is good to make you more approachable and to help with that shyness.
As for combinations, there are many good ones, but you really need to become familiar with the efects of each one individually so that you understant them, before using them in combinations.
This post should help you understand about that: