Do a little research on the publication you are sending in to before you send to them. Read their sample poems, if they offer any. Read the editors' bios and mission statements. Many editors I know go so far as to say you should learn the editor's name(s) and address the editor(s) by name in your e-mail or letter rather than writing a generic "dear editor(s)."
This shows an interest in the publication and it shows you've done your homework before submitting. It will also help you find publications in which your work will be a good fit.
(To Be Continued)...
Check back each day this week for a new tip.