If you're going to fight the higher rappelz-item.com/tag/level/">level mobs, don't fight too many. There are mobs that have an aggro range. Do not pull these then run off and fight something else unless you are prepared to fight all of them. Don't be afraid to chip. Chips are easy to get and you will gain enough lak by the time you are done to probably gain back most of what you have used.
This works until you hit R4 and can't purchase chips with lak anymore. After R4, our best suggestion is just to chip at your own discretion, since they actually are costing you money now and you might be saving them for a DP. For everyone else who isn't R4, just remember, you are probably farming mobs higher level then you and this will make it tons easier to kill them quicker.
Bring Pots and Scrolls, because you are going to need them. Unless you want to spend a majority of your time sitting on your bum gaining HP or running around looking for a healer, you need to do this. If you do not, you will spend most of your time pushing daisies or sitting around.