profile managing help

this is sounds like a very easy problem i'm encountering, but i cannot
find a solution.

the problem is that last night i opened up a new profile for the heck
of it, but in the process of wanting to go back to my old firefox
browser and profile i can't find how to switch back and forth. i've
checked and checked the mozilla site--it dosen't help.

why is this so elusive? any help