Just a quick post before bedtime. I'm pretty low-level myself, but since being level 1 is much fresher in my mind, I thought I'd pass on some advice.
Partying. For heaven's sake, start partying early. After level 5 or so, solo xp is going to begin drying up. You're better off in the group, and partying early will allow you to learn good partying skills, such as:
1. How to skillchain. This isn't that hard to learn, there are tons of FAQs on the subject
2. How to expchain. This is really simple. Kill things one after the other.
3. Proper hate control.
So try to start partying around level 7-8, instead of waiting until you're 12 or something. Also, since being in a party is such a necessity once you start really playing the game (really, the game doesn't start until about level 15 or so), here's a good way to make yourself attractive to a group and get good parties.
1. The most important thing is YOU. How good a player you are, how well you do your job. Know your role in the party, and stick to it. If you're a warrior, provoke. If you're a thief, stay behind the monster at all times, and watch the timer on your sneak attack. Remember that you can use sneak attack with certain weapon skills, like fast blade. If you're a white or black mage, please don't melee. In fact, try to stay a good distance away from the monster at all times. Communication is essential, also. If you're silenced, tell the party. If you're low on MP, tell the party. If you suddenly have to leave to go to the bathroom, tell the party, so they don't end up pulling a creature thinking you're going to be there to help and you aren't.
2. Subjobs and race are important to performance, and you should strive to be the best you can be at what you do. But don't obsess over it. I don't know of too many people who will outright refuse someone because they're, for example, a tarutaru monk. Spend more time worrying about your tactics, working on your macros, and upgrading your equipment. I'd rather have a smartly played Galka White mage in my party than a tarutaru white mage that's a complete doofus. Doofuses are what get you killed.
3. Speaking of getting killed...nothing breaks up a party faster than sudden death. People start blaming each other, or suddenly remember that there are other things they want to do...the party drifts apart. Avoid unnecessary death by having an escape plan. When you form the party, come up with a procedure for what to do if an aggro monster shows up or if the monster you've targeted turns out to be more than you can handle. Make sure everyone understands the plan. Also, try to find the nearest bind point and save there. I know this sounds simple, but I've seen so many people levelling in the Shakhrami Maze who die, and end up waiting forever and a day for a raise because they were saved in Jeuno. Also, if your bind point is only a zone or two away, don't raise. It's a waste of the white mage's time, and a waste of your's, since it'll probably take them longer to come find your body than it will to simply walk back to the party. Most areas you'll be farming from level 1-20 are easy enough to get to. Raise is a high level spell because it's meant for people who are in the areas for levels 25 and up.