Always double-check hyphenation
Always check for properly hyphenated words.
Watch out for situations where words like "therapist" are split into: "the" and "rapist."
Limit hyphenation to two consecutive lines. When too many lines in a row are hyphenated, it's a clue that your type size is probably too large for the column width you have chosen.
Avoid hyphenating proper nouns, like names or places.