I have tried calking a place in our shower three times with silicone calk, which I thought was the proper type. I let the shower dry and did not use it for several days after applying calk.
After about a week, it bubbles up in the corner and it separates .
Am I using the proper type calk, or what else am I doing wrong?

God, I am going to love seeing these answers, because by husband did a terrible job caulking our new surround and its going all black and impossible to clean even with a toothbrush!

Thanks for posting this, trippsdad !

Did you both use 100% silicone? It resist mold (black stuff). Slice tip at a 45 angle and caulk up your seams, don't attempt to spread with your finger. Just let it dry then with a razor trim it up.