As you're leveling, I generally recommend you just follow the natural flow of the progression through each zone. They're laid out fairly reasonably. But don't be afraid to hop around, especially if you're near a quest objective. You shouldn't actually need ALL of the zones listed to reach 62. Pick the ones you like best. It's much more important to simply be as focused as possible and flow from one quest to the next.
This is also the reason why when I read in WoW forums of people skipping guide sections, due to being too low level I'm not agree and start ranting about it: it'll be a mess syncronizing with the guide and I've seen many people complaining about missing quests or accusing the guide for being innacurate, but not realizing that was their fault since they're skipping and missing a lot of quest chain requirement. Of course this apply if you're following a guide, believe me, it's very frustrating when you remain stuck in a guide section due to the reasons I've mentioned, more than doing grey quests (but they allow to be perfectly in sync with the guide) and goiing here and there to get the pre-requisite quests.
Level with a pet if you can because it will help keep you safe. If your pet is tanking all of the damage from the enemies you’re fighting, you won’t have to. The other reason is that pets are easier and cheaper to heal than you are. If you don’t have a pet, make sure you know how to use your defensive abilities. You can’t level quickly if you are dying all the time.
Galakrond-Alliance-USGalakrond-H-USGarithos-Alliance-USGarithos-Horde-USGarona-Alliance-USGarona-Horde-USGarrosh-Alliance-USGarrosh-Horde-USGhostlands-Alliance-USGhostlands-Horde-USGilneas-Alliance-USGilneas-Horde-USGnomeregan-Alliance-USGnomeregan-Horde-USGorefiend-Alliance-USGorefiend-Horde-USGorgonnash-Alliance-USGorgonnash-Horde-USGreymane-Alliance-USGreymane-Horde-USGrizzly Hills-Alliance-USGrizzly Hills-Horde-USGul'dan-Alliance-USGul'dan-Horde-USGundrak-Alliance-USGundrak-Horde-USGurubashi-Alliance-USGurubashi-Horde-USGallywix-Alliance-USGallywix-Horde-USGoldrinn-Alliance-USGoldrinn-Horde-US