Cap Poetics, cap Scripture, set aside any dungeon pieces you'll want for glamour or any dungeon gear 55+ (so, from the Aery onward as that was the point dungeon gear>Poetics). Clear a save slot in PotD. Save up your GC seals, and for good measure, stock up your hunt seals too. If you own an FC, ready up some rainy day XP buffs. Make/buy leveling food and set that aside.

Last but not least: Network. Find some friends/players on your server who you might want to form a stable leveling party with. Find a dedicated tank/healer, if you're going RDM, find someone who's gonna level SAM, or vice versa. If you have a tank/healer you might want to level as well, work out a rotation where you all swap roles. It'll be more fun to level together in a group you know and can count on.