Muse?

I'm thinking of becoming quasi-serious about writing something literary in nature, hopefully of actual literary merit as well.

Does anyone have any useful tips for how to go about this process? I'm not thinking Russian anecdote (a couple of hundred pages or so) in length, more like a novella or short play.

I have only vague ideas in my mind about the sorts of things I'd like to write about, chiefly something of a dissident nature. But I'm wondering if anyone can recommend ways of getting underway, aside from sketching out some rough ideas and trying to piece together a clearer picture. Any help will be welcome.