Start as a one-handed user with a shield. I would avoid a spear initially. Go for a build of ~ 21 str, 15 agi. You should fine a similar build somewhere here on the forums for one handed. Don't take riding or throwing, just stick to basics. Read all the guides around for the class to get an idea, and then jump into the servers.
I cheated and practiced mainly with a clan to teach me, and siege were I can respawn and get more practical experience. Now, the reason I say to pick a one-handed shielder is so that you don't have to worry about manual blocking. You first want to get in the habit of simply reacting to an enemy attack first. Stopping arrows is just a plus. As a shielder, you can learn footwork, wish is how to use the movement system in the game to make your attacks connect quicker. (Example, swing left to right and moving to your right)
If you really want to get better quicker, take a 15 minute warm up in single player. Not the campaign, but boot up native and start the tutorial. Run over to the combat trainers and ask them to spar. During the spar with the npc, dont attack and just block. Block as long as you can. Start with novice trainers on low speed and work your way up. Manual blocking and manual attacking in this game are one in the same, and all of it is based of muscle memory. How do you build muscle memory? Repetition.
Be persistent in what you do and you will succeed. Though it is funner, and I admit I did it, try not to try out every single class early on. They all work differently. You'll spend so much time learning each class' specific things you will forget the basics. (No one will teach you the basics when you ask how to play Class Y.)
Once you have the basics down (Footwork, Manual attack/block) you can do almost anything in the game. Good luck.
P.S. As I mentioned I cheated by having a clan help me, I advise you do too. Having mentors definitely changed my cRPG experience.
