[Agua]

I would add this: protect your fucking medic. Pay attention to their health bar on your screen. If you see them taking damage, turn your ass around and kill the bastard going after them. Experienced players know to take out the medics first. I find that if I run past someone being healed, many times they tend to go about their business leaving their precious medic completely vulnerable.

Also, medics, don't forget to heal engies every time your run past them. That little extra can mean the difference between losing all their buildings or just one.