Come up with far more than you think you need. A longlist of thirty to fifty candidates works best.
Sounds like a lot, but the first ten are always the obvious ones. You'll come up with those without effort. The real finds sit between the twentieth and the fortieth. Those only come when you stop thinking in patterns.
One tip: switch modes while you're brainstorming. First five minutes of regular brainstorming. Then five minutes of compound names only. Then five minutes of names starting with a verb. Each switch kicks you out of your habit and gives you new angles.