I get some weird emails as an editor. People telling me their life story, how they don't think their writing's any good but thought I might like it, how brilliant they are (followed unanimously by a totally pish poem/story), or just saying nothing at all or calling me by another name. Here are some tips, writerly folks:
1) Say hello
2) Keep it brief but polite
3) Don't put yourself down or big yourself up too much
4) Follow the guidelines
(and preferably, but not absolutely:
5) show some interest in the publication
6) get my name right)
Here's an example of what I might send:
Having recently read and enjoyed YOUR THING, I thought I'd send MY THING for consideration for publication in YOUR THING.
I hope you enjoy my work (brief bio below - if they asked for one) and look forward to reading the next YOUR THING.