1 : Any cheap food, but honestly, at 3% it won’t amount to much. Early on, its very difficult to do so outside of being lucky, but going from 0 Quality to max Quality within the crafting (IE - Quality from HQ materials does not count towards this; in fact, Quality from HQ materials reduces this) you get 300% bonus exp, or four times the base exp! 3% is paltry compared to this. Even the 50% from Rested is paltry compared to it.

2 : those manuals are awesome for fast crafting. Make a leather/ingot/thread, then Quick Synth about 20 of the things per Manual. There are three levels of manuals, I believe the first level manual (1-50) is from the Grand Company vendor for a small sum of GC Seals.

3 : power leveling crafting, and doing it the most-gil-efficient way, are pretty much contradictory.

The most gil-efficient way is to gather all the materials yourself and to make everything once, two or three times if it is something that you can use yourself, or for a Leve. There is a lot of experience waiting in the Crafting Log that most people ignore in favor of faster leveling practices. Selling what you make that you don’t need to use can actually turn a profit while crafting, even if you buy a few materials.

The fastest way to level is the most expensive : buy HQ stuff off of the board to hand in for Leves. Unfortunately, you only get 3 Leve Allownces every 12 hours, so once you’ve burned those up, it takes some time to rebuild a suitable supply. The Leve Allowance cap is 100, you’ll never have more Leve Allowances than that.

3 : Camie’s guides are pretty good from what I remember, but I don’t know whether she’s been keeping the older ones up to date with the occasional changes that occur (such as the pretty big ones with Shadowbringers, removing Steady Hands 2 and Byregot’s Blessing from the Cross Class list and making unique versions for each class).

4 : it is generally best to avoid melding materia to leveling gear overall. The gear doesn’t tend to last all that long. In my experience, raising all the classes up together usually fully spiritbonds the gear, leaving only the MH/OH tools under 100%. With the ability to remove materia from gear, melding some CP to the gear’s open slots is not a bad idea, you just have to remember to remove it before converting the gear itself to materia. As long as you are using the highest level HQ gear that you can, however, melding while leveling is NOT necessary.

5 : RNageo answered this best.

6 : Many of the level 15 Cross Class moves are valuable to have. I’d suggest taking each class to 15 specifically for that move. Then take them up based on materials, or in 5 level increments. Once you reach expansion levels (51+) materials increments will only be two-three levels but you’ll need a lot of those materials within those levels. So, I’d suggest using Retainers to help you get your materials. Combat retainerscan get your skins and various odds and ends. Miners Botanists andFishing retainers can get those types of materials. ITs your choice what retainers to use, though I’d suggest combat retainers if you ar only using two. You don’t tend to need a lot of fish, and while you do need a lot of ores and plant materials, those are usually easier to gather in bulk than mob drops.