Sometimes people ask me if I get "designer's block" or run out of ideas, and the answer is "no!" I have so many ideas I have to keep a list/sketches of what I want to do when I get the time. Occasionally though, I am asked to design something with a particular yarn or design a certain type of item, like a baby afghan or a toddler sweater, and I have to stop and think. Maybe I didn't have any ideas in my sketch book that would work, and I find myself with hook and yarn with no ideas.
I think the worst thing that I could do is get nervous. I don't need to psych myself out! I really truly "trust" that something will come out (good or bad) and that I will be able to spring forth from there and find something that I like (even if the editors don't!).
My first step when I am sitting with hook and yarn and no ideas is to:
Without expectations, without commitment, without a plan. Just start and see what happens. If I sort of like what I make, I'll fasten it off and set it aside to explore more. If I don't like it, I frog it and start in a new direction. Eventually, I believe something worth while will come from my time. (And it doesn't hurt to pray a little...)
Here's a quote for you:
"Amateurs wait for inspiration. The rest of us just get up and go to work." Chuck Close.
or to quote another obscure source: "Just do it" (Nike, of course)