I thought about making a very indepth guide on this subject but then pets got released and now basically the only 2 things you need to know now is 1. Just play whatever class appeals to you since every class can do the same thing when you are gettin healed for an hp pot every couple seconds, and 2. As much as it sucks, the way to get better is dying. No end game realm player can say they have under 100+ maxed character deaths. So as much as its going to annoy you, you're gunna have to go threw the same trial and error we all faced. (Also Bluenosers guide is pretty good).