I would suggest doing all the quests in Uldah after switching to GLD. With rest XP and a moogle hat (if you have it), you will get close to level 10 just from these. Then with your hunt log, it should put you over 10. Then start up with fates until you can work on your Main Story again.

That is, unless you want to use fates to level from 1-10. Either way works.