The way I learn my classes when I feel like I'm unfamiliar with them is basically to do a combination of 1v1ing with people who are better at the class than I am, and experimenting in rpk.
Every death is a lesson. Learn what gets you killed and what gets you kills. If you happen to catch any of my Cynix characters in worldchat, feel free to pm me for a 1v1. I'll log any character you wanna practice against and give you a few tips along the way. Good luck.
I agree with this completely.
Also; people may disagree but trying to test the waters on Nightscream island is a good way to learn the feel of your class as well. You may get ganked by legions of thousands, yes, you may want to ragequit the instance constantly, yes. However, at the end of the day the players who usually stay and PvP on NS aren't the "Top-Geared" players on the server and it's a fair match for dragon/low r8 statted players.
I always do this because I learn how to PvP better on my classes when not fighting players who have played for years.
