DON'T send a boilerplate email, à la "Dear Professor, I'm interested in your research area". That's a total turnoff...
DO show you really are interested in the professor's research area, by writing a personal email that demonstrates you have spent at least 5 minutes (hopefully more) exploring their area. And for crying out loud, at least add their name: "Dear Professor Dumbledore" rather than "Dear Professor"!
DO (briefly) describe your industrial and academic experience.
DON'T be overly lengthy. Two paragraphs should suffice: one for point (2), one for point (3).
DO be polite. (Duh...)
DO or DON'T attach a short CV. Up to you.
DON'T attach anything else. If there's an interest you'll be asked for additional material.
