Indeed. Hunt down ranged while flanking.
It's your top priority.
Also, if you enjoy assassination, like I did in my Cav days, try to take out the top players of the Enemy team, or Horse Archers.
Your team will love your for this, as you drastically increase chances of a victoire.
Do as much damage as you can. Couch into shielders for fun, and to weaken their Huscarl shields, it will hurt them heavily, and your mates can open them persistent facehuggers much faster.
For cav vs cav, do what everyone said, turn, turn, turn. Learn your effective speed, manouvering ability is a must. Always, I mean ALWAYS slow down when you turn around, it will take less time, and can give you the finishing blow against an enemy horseman who just pressed W+A/D like an idiot. Learn the range of your lance, obviously. Practice releasing before you meet the target, you will feel when to do after some time, I can assure you. Don't be afraid of Couching: It is your trump card, use it wisely.
Don't be afraid of straight charges either! Sometimes, it can shake the enemy, and for once, you fought well, with glory and courage, to strike into a wall of ranged, and pole weapons. The risk is high, though, but if you manage to kill an MvP while you do it, it was well worth it.
Also, learn how to annoy the enemy cavalry, when they pursue you. I managed to annoy 10 enemy cav for 5 minutes in native, they weren't able to catch me, I just had to circle around them, and use their predictable movements against them. It's so much fun, I always enjoyed being chased.