I'm fully aware that I'm walking into an inferno by posting something that feels like such a stupid question, but I'm just clueless, and yes, I used the search function and didn't see anything.

I picked up a '7-Color Blinking LED' at RadioShack today, and rather than the 2 stems it has 3, and sticking it to a regular 3v watch battery I get the generic R/G/B+Mixes. However, I don't know what that 3rd stem is for, and I'm assuming it's to control single colors, but my question is, how?

I also picked up a 'Full-Color LED' that has positive stem + 3 others, 1 for each color, how could I wire this?

I just don't know what type of switch to use to light it. Could I get a switch that cycles through the colors each time I press it?