Rested Bonus +50% XP
Engineering Manual: +50% XP
Food: +3% XP ^^;;
So up to 103% bonus XP.
You can get rested xp from sleeping in your inn (longer you sleep the longer your bonus lasts).
You can get the manuals from your grand company store (400 seals gets you 9000xp worth of manual)
You can buy food in the wards or shops (they also boost your skill to make it easier to craft).
Levelling on a craft equal to your skill will be (I THINK) around 300xp, but if you level on one higher that will be of course more (easily goes up to 1000+ per synth).
If you can choose a good craft about 4-5 levels higher than you, you should be able to do it with JUST standard synth. If you add a little quality into it as well you will get a lot more bonus XP.
