The only way to have more good ideas is to not be afraid of having bad ideas.
Because the more ideas you have (no matter whether they're good or bad), the higher the probability that some of them are going to turn out to be good ideas.
Here's the thing...
You might think you know what a good idea or a bad idea is.
But the only way to really know it is to put it out there.
And quite often those good ideas turn out to be bad ideas.
And those bad ideas turn out to be good ideas...