The phrase "it's not worth ___" is useful for telling people not to do something:

It's not worth getting upset over.

This means "You shouldn't get upset over it, because it's not that important."

When you use "not worth ___", it means that you don't think that the reward for the action is high enough for the effort or risk. For example, imagine that your friend really wants to go to a music festival. He suggests skipping work to attend the festival, even though that's a really important, busy week at work. You might say this:

I'm sure it would be a lot of fun, but it's not worth risking our jobs over.