Personal preference:

#0 Use macros. After a summer overseas with bad internet, it's just too damn exhausting to manually craft all the time. I'm macro-ing now as I type.

#1 All Lv15. Cross-class skills Hasty Touch and Careful Synthesis are your staple until 60+; some like Rumination and Tricks of the Trade, too.

#2 CUL Lv37, CRP Lv50. You want Steady Hand II for more skill success rate. You NEED Byregot's Blessing for its HUGE Quality boost. (It bumps your HQ% and EXP% bonus UP.)

#3 Whatever you can tolerate. Grind if you have the mats; get friends who can craft you HQ leve items. You can go surprisingly far on mats, but it's still better to turn in a NQ leve item than to let your allowances go to waste.

Happy crafting!

NOTE:
* Moogle Dailies are INSANE EXP; very efficient from 50-60.
* Put up a party in PF for advice. You can get crafting mentors this way! My friend got a response in 5min.
* Collectibles are hit or miss.