Yeah you hold the bomb in your hand while setting the source, and then after you've set the source, you place the bomb as a structure by right clicking. All structures that require a source or a target work like this, so things like the logic gates. The bomb can also be put inside the press to automatically detonate it.
I don't have the capacity at the moment to make a full tutorial of the game, but if someone wants to take that task upon themselves, go for it.