Brainstorming Methods

So you want to write a lyrical piece. Do you have any more specific preferences beyond that? Something you care about or are interested in and want to write a lyrical piece about?

If you begin with a hint of an idea, you can continue to generate more specifics to narrow down the idea and come up with details for your piece.
"I want to write a lyrical piece" is way too unspecific.
"I want to write a lyrical piece about compassion" is getting somewhere. From that point, you could ask yourself how to convey the idea of compassion. You would then brainstorm situations where people would demonstrate compassion, or not. You could brainstorm types of characters who would embody the theme: someone who learns to be compassionate, or someone whose compassion goes unappreciated, for example.

But if you don't have even that hint of an idea yet of what you want to write about, it's like wanting to talk but having nothing to say. I don't think you can force inspiration. If you don't even have a bare hint of a topic, you might have to wait for some belief, value, or life experience to motivate you on its own. I've tried writing without caring about my idea before, and it was joyless and forced and I didn't finish what I started.