What's the best glue to use for attaching foam to pink stuff? I'm putting together my first stamps and I want to choose something that will hold up. Thanks!

I like Gorilla Glue. Spread a very thin layer onto the stamp (and I mean very thin because it expands and could ooze out where you don't want it!). Press the foam onto the stamp and place it carved side up with something weighty on top of it to dry overnight.

I use Gorilla Glue too. I cut a few shallow slices on the back of the pink stuff and then use a couple of small wooden boards (that I got at wal-mart in the craft section) and some of those large paper clip things with the springs to hold it together while it dries. Works really good, but yes, use a thin layer of Gorilla Glue or it will seep out. Also, it will fill carved out places in the rubber really well while still being pliable, so you can mount a new stamp carved on the back of a stamp that you want to retire and/or you screwed up when you were carving it the first time.

Doesn't gorilla glue need water to activate it?

Doesn't gorilla glue need water to activate it?

No.
The bottle suggest wetting one side but it is not necessary. It is very slick. The two pieces being joined can move if not held in place. It also dries hard reducing the effect of foam cushion. Up side it is waterproof.