Before I worry about meter, rhymes, rhyming patterns, structure, middle eight and all those other things that are inherent in writing lyrics I want to know what the story is i.e. what it is that I want to say. It might be as simple as creating a song around an emotion ( usually love, but it could just as easily be loneliness, or loss, or anything). Or it may be a character study. Or (preferably for me) a proper story - be it a love story, a motorbike story, a tragedy, or something involving cowboys and pretty girls in gingham. But the thing is, until one knows what one is going to write about it one can't write.
So, what's the story or emotion or theme? Armed with that I'm sure we can help!