Started a new combo - Warrior/Paladin advice

(I posted this in the general section in case there is someone who posts there that doesn't come here, but if it is against the rules, I'm sorry. Don't see why it would be a problem though)

I've started leveling a paladin and warrior team, and I am wondering the best course to dual box. I don't know which specs I should go to make leveling the easiest, and I surely do not know which character to make the main, which probably depends on the talents as well. For example, should I use my paladin to tank and warrior to dps, or warrior to tank/dps and paladin to heal, or a combination of both where the paladin and warrior both dps and the paladin spot heals. I can't find any information about anyone else doing this, so I am looking for some much-needed help. I am brand new to dualboxing, but my first set will be paladin/warrior, and I am looking for advice. Thanks!