Well, first let me say that I am pretty lousy at AA combat...so I can give you some THEORY, but damned if I am good at practice!
1)Jamming
Sometimes jamming is the WORST thing you can do. JAM a radar SAM or RADAR AAM or JAM to break a lock (and maybe avoid a SARH missile shot), but if you have jammers lit,you are giving your position away to the enemy and he may have HOJ missiles too.
2)Radar
By definition, the Radar Warning Receiver will pick up radar signals at longer distance and greater aspect than a radar lock, so your RWR (and the enemy's) can tell that there is a hostile out there,and the approximate bearing. Staying radar silent and making use of MSI datalinks as much as possible will shield you from detection. Just because you pick up an enemy on the RWR doesn't mean he has seen you (unless of course you get a lock indication...) So if your radar is silent and you catch a hint of a radar transmitting, you can go on the offensive (or defensive).
Take advantage of the radar cone and try to stay well above or below the enemy's estimated altitude (which you might get via AWACS). GENERALLY being HIGHER is better, as it gives you more energy to maneuver and gives your missile slightly longer range, but it could make you a sitting duck for ground based radars.
Flying VERY LOW will get you past many threats (except AAA) if your goal is to evade fighters and head for a target. If your goal is counter-air,then being very low can be a handicap since your missiles are now shorter ranged and will burn a lot of maneuvering power just trying to reach altitude.
Try to take a BEAM position with the enemy on your 3-9 line. Not only will this frustrate radar locks, but will frustrate missile radars AND to some extent give you more room to outmaneuver heat seekers.
3)Terrain
Use terrain (mountains) to hide from enemies. Their radar can't see through terrain (neither can yours) but if you have an idea of enemy position by RWR or MSI you can shield yourself on approach.
OK, that's about it. Of course the AI will try to use these tricks against you as well...but not quite as well as another human pilot.