One thing I tell my students is to try reading your work out loud. Would you actually be able to "speak" your writing. Here are some more tips:
*check for the passive voice (the indirect format). The always sets you up to write wordy
*eliminate wordy phrases such as "due to the fact that", and "I am writing you to tell you that"
*avoid lawyer-like writing (herewith, the undersigned, heretofore etc).and other gobble-gook like phrases.