Why not have a read of this:
https://pheromonetalk.com/t/how-do-i-qualify-for-a-25-gift-certificate/19934
Then go and post a new thread in the Intro forum, giving a bit more info about yourself and your situation.
That way, we have the info needed to offer some better advice and you earn yourself a useful GC to offset the cost of your trying them out. 
And this thread covers just about all the basics you need for choosing and using pheros effectively: