When all else fails, just start writing. Or designing. Push back against the idea of not having any ideas.
Write headline after headline after headline. Page upon page. Try writing the first paragraph. Try writing a page of theme lines. You may come across words you didn’t expect. Write the set-up speech for the idea you don’t have yet.
If you’re trying to write a film or video, write a radio spot instead. It’ll give you sixty seconds, twice as long to spell out your proposition.
By beginning the process of writing, you will discover ideas along the way. Don’t confuse movement with action. They’re not the same things. But sometimes, in lieu of action, making a little movement is the next best thing.