My newbie guide would be this. Stay in the first zone as long as possible, make sure u do every single quest, and repeat the ones you enjoyed a few times. Also you need to do Polaris a few times, you need at least a few good blues from there before you move on to the next zone. The little tokens you get can also be used to buy a blue from the guys near the police station. The second zone will feel a lot easier once you have those few blues from the previous place. You can also just go back there any time you want and do the missions again or find any you missed. The mobs are easier there and the quests are easy and I found it quite a nice place.
Then in the second zone, try to do all the quests you can find and do Inferno as often as possible, preferbly get yourself a few more blues from that place. You basically need the blues from these dungeons to allow you to do ok in the next dungeon of the next zone. If you rush ahead you'll struggle. You also need the XP to unlock lots of good abilities and the high end ones. That first zone has some quests near polaris which give a ton of exp. You can repeat them every day and they are pretty easy, especaily when you have already done it before. Load up on xp in that place. And do polaris until you get some gear or get bored. Bad groups happen but try again.
With the skill wheel, you need to learn it and work out ones that mix together well. For example you might be using blood magic and shotgun, but there might be some passive from the assault rifle tree that would really help. You need to mix and match this stuff intelligently. And nothing is wasted, because eventually you will want the whole tree filled anyway. It looks complex at first because there is so much to see but sadly its quite simple because thats all there is - ever. For example, there are only a few ways to do healing - blood magic / assault rifle are the main ones and thats it.
You need at least a few builds. You need a build dungeons that is pure dps or pure healing or whatever you want your role to be. Dont try to do multiple things, if you are healer they dont need your dps, you just need to keep everyone alive and the dps can focus on the damage. But you also need a different build for soloing which has some area damage abilities (because fighting groups of mobs is common), and you have to have some heals because it just makes soloing far easier if you are healing yourself while you fight. Experiment with stuff, you should be able to make a super heal build that doesn't do much damage but heals you strongly so you just chip away at mobs and eventually the die, but you are almost unkillable. Then tweak it a bit and add some more damage to it.
And, you need different sets of gear for each build. For your heal build in dungeons, the heals wont be strong unless you have heal gear. And same goes for dps and tanking. Once you go solo questing again, you should really wear a mishmash of gear, almost half tank items can help you survive better, and then about half heal items make your heals more effective. Maybe one dps item or whatever. You can get by soloing with a pure dps build a bit later on, just kill mobs asap and then you dont really need to tank or heal. But at first you might struggle to kill things fast enough so its probably safer to have lots of heals to make life easy.
Also try the different weapon types just to see what you prefer. Once I tried assault rifle I loved it because you kill stuff miles away which made things much safer. Shotgun was stronger but stuff gets closer to you so you need to kite more. Elementalism was good for doing a lot of damage to single targets. Blood magic was just all round awesome because you heal yourself and it also does some good damage too. But some people like pistols while they kite all over the place. I preferred a more lazy approach of standing still and pwning stuff with minimal running around. You can make it work however you want by tweaking your gear and build.
