There's not too much advice that can be given tbh.
Just always move when you cast your instants, only use less than 3 HP-WoGs when you know you wont have time to get an additional holy power before you die. Try to position yourself in the right place to avoid your opponent having an advantage over you.
Don't mind using a bandage between your enemy's attacks if you know you can get at least one tick off, or use a bandage if you've been interrupted.
Fakecast properly. Know when to fake and when to not fake. If you fake until they interrupt you will die if they don't interrupt, obviously.
Always have your enemy in front of you when you're not casting to avoid the melee attacks. When you're casting vs a higher level rogue (16+) make sure he can't get in front of you to gouge when you faked his kick.
Only mages can interrupt at level 10, it's a 8 sec lockout and you'll probably get killed in it if it hits you. Now is the perfect time to use lifeblood and bandage to get quick heals off.