5-10 deodorizer - all items NPC purchased, use ffxi.cannotlinkto for NPC locations.
10-20 echo drops - farm honey with a 15 THF subjob, one shot bees outside bastok and use /ja "Steal" every time its up. buy sage from NPC in sandy.
20-29 silent oil (olive oil recipe) use beechips from honey farming to make wax, buy olive oil from NPC, much cheaper to break than slime oil, and a higher skillcap.
29-30 artificial lens - you should come up with gob masks while farming all those damn bees, crack them for glass fibers and sneak that one skill lvl on lenses. you can AH them afterwards, or set up a bazaar. this caps at 34 but don't bother going past 30 because...
30-40 potion - sage from NPC again, liz tails from AH, or by god just farm them, you can't spit without killing a gustaberg lizard and getting a tail. these are a pain in the *** to move for gil, but the ingredients are cheap. to offest the loss, i made a /item "Potion" <me> macro and sort of self-PLed my ninja to 10.
40-50 holy water - stupid stupid cheap. just grind it out at the guild and sell the stacks or NPC them and eat the minor loss.
50-56 sleeping potions - farm your shrooms at the Tumbling Truffle spawn, then camp out in the back of the goblin shop for the synths, since poison flour doesn't stack. sell your stacks of potions for a tidy profit.
56-60 glass fiber (8 x Flint Stone + Fire crystal) farm these from worms, or choco digging, pester your friends not to throw them out, or just /sh to the newbs in zeruhn mines, they will have plenty for sale. you will make money if you don't pay AH price for these.
ok, so you notice that i craft on a ten level gap. make sure you get guild support for the first 3-4 levels of your gap, and craft on days to which your crystal is strong. after reaching the 5-6 level gap range, you can do your synth without support, meaning you can take your low level job and some liz tails/sage into the field and skill up as you make more potions.
if you want to go past 60, i'm working on Brilliant Snow to 70, since sheep leather is pretty simple to farm, glass fiber should be stacked up from your flint stones recipe, and the rest is all NPC bought.
70-75 you can do anima if you have a way to farm the promyvion, as well as the key item, and after that bloody bolt heads to 81, but you'll want to farm the blood, and for that you want a 45+ THF at pashhow marshlands.
beyond 81 is anyone's guess, but by then you should be able to figure something out.