There comes a time when it's just not coming out. The creative juices: they just aren't flowing.
So, how do continue creating when you're feeling tapped out? Easy. Robert and I have used one foolproof technique throughout the years, and it's never failed us; a chord encyclopedia.
Assuming that you are using a guitar to write new songs, a Guitar Encyclopedia can be your best friend. The Guitar Encyclopedia's use is actually two-fold. Using it, you can assemble a new song. You can also push yourself, technique-wise, through finding new (or forgotten about) chords.
Robert and I have created beautiful songs with this technique. We find the crazy suspended fifths. But, we also find five billion versions of a G minor chord, one that might be close to another interesting chord. I advocate playing around with this idea. You might find yourself pleasantly surprised.
I know that Robert's going to correct me on my usage of those chord examples. He'll usually do it in passing, too, like when he passes me in the hallway or something.
Bet I just made him smirk.