Being a warrior is hard when you start. Low level warriors do pitiful amounts of damage and don't have much more HP than other classes. Depending on skill choices, you could have an extremely difficult time or just a tedious one.

Warriors have skills that are common to all of their weapon choices, specific skillsets to three different weapon choices, and support skills. Let's go over the choices available to low level warriors (up to level 20):

Shatter - An excellent skill available right at the start of warrior-hood. It stuns your opponent and does a little bit of extra damage. (I didn't take this and definitely wish I had)

Skybreak, Meteor Crash, and Royal Blow - These three skills are the short blades, heavy weapons, and long weapons respectively. They do a single strike that does extra damage. While not very good skills on their own, obtaining 4 levels of them opens up possibilities at level 36, and further levels open up further possibilities later on. As for these skills themselves, they're really only useful to start combat against passive opponents. Get one of these when you can, but don't make it a priority.

Howl - Obtainable at level 5, this skill increases the max HP of you and your nearby party members by 80. It can be upgraded at level 20 to increase the max HP of you and your nearby party members by 200. It's a very useful skill, especially when helping mages. Get it.

Provoke - This skills increases the likelihood of an opponent attack you instead of someone else. In other words, it transfers aggro. Be careful, though...it doesn't always work. Some opponents will still chase that poor elementalist around 'cause he's doing so much damage...

Bless, Victory Strength, and Speed Attack - You can get them at level 12. Make sure you have 6 points by then and get them all. I promise you, you will not regret it. Two of the three last for 10 minutes (the other only for three) and all have a cooldown of 5 minutes...but all of them together grant a huge boost to defense, a minor attack boost, a huge attack speed boost...and slightly decrease your regeneration rate. Speed attack especially increases your damage output, which you sorely need at a low level!

That's all for the low level warrior skills. My advice? Get Bless, Victory Strength, Speed Attack, Howl, Shatter and Provoke...and worry about them in that order. You'll be using those skills throughout your career as a warrior.

Good luck!

Oh yeah, one last thing...When it comes time that you want to choose a weapon type...

Short Blade = tanking.
Heavy Weapon = damage.
Long Weapon = multiple enemies (though it takes a long time to get those abilities).