Crafting has changed a lot, what with the changes to how skillups work, introduction of RoE items, and mat price/availability changes. Most of the old guides aren't relevant anymore.
I'm going to make a new Goldsmithing guide 1-110 and obviously anyone is welcomed to toss in guides for other crafts.
A couple of general notes:
* Always use Kitron Macarons
* I prefer to start synthing something when I'm 5 levels below it (with advanced support) and then will take it past cap if it's useful or particularly cheap. Sometimes you end up with longer gaps than that, but it's not ideal.
* There are now two guild NPCs. One of them is always open and sells kits and mats, but the materials are typically more expensive than the least expensive normal guild NPC price. Buy from whichever has the item for cheapest. Not all items are available on both.
* Change your job to WHM or RDM and set the 30 synths RoE quest. You eventually want to be level 70 on this character so you can wear a torque. RoE quest won't get you there, but it will get you to 25 or 30 so you can cast Sneak/Invis.
Your major cost with this guide is going to be Crystals. There is somewhere in sky with 4 elementals of a given type close together, and you can just farm them over and over for clusters. You get about 1.5-2 clusters/kill with TH, so it takes about 2 hours of farming a given element to get 10 stacks of clusters and you will probably not need anymore to hit 110.
Fire: The area near Faust has 4 fire elementals on a ~5 minute repop timer.
Wind: One of the corners on the first floor has wind clusters, iirc.
* Mythril Ore
* Elemental Ore
* Orichalcum Ore
* Guild Points
1-5: Copper Ingot (Copper Ore x4 + Fire Crystal) : Buy Copper Ore from a Guild NPC (don't use the kit)
5-10: Brass Ingot (Copper Ore x3 + Zinc Ore + Fire Crystal) : Buy all mats from the NPCs
10-15: Brass Sheet (Brass Ingot + Fire Crystal) : Use up the Brass ingots you just made
15-23 : Silver Ingot (Silver Ore x4 + Fire Crystal) : Buy Silver Ore from the Guild NPC
23-27 : Silver Hairpin (Silver Ingot + Wind Crystal) : Use up some of the Silver ingots you just made and NPC these
27-35 : Spark Spear (Brass Spear[RoE] + Copper Ingot + Fire Crystal) : Use up your copper ingots and NPC these
35-40 : Mythril Ingot (Mythril Ore x4 + Fire Crystal) : Try to buy these off the AH. If prices for mythril ingots on the AH are cheaper making them, don't take this past 36 and just buy ingots to turn into sheets off the AH. Goldsmithing 40 kits may be price-comparable to ores depending on the server.
40-46 : Mythril Sheet (Mythril Ingot + Fire Crystal) : Convert your ingots into sheets. If Mythril Ingots are cheaper than 20k/stack on your server, keep buying more and converting them for free skillups, as sheets NPC for like 1.8k each.
46-58 : Geode (Geode + Wind Crystal) : Hopefully you stockpiled these. Grind them out.
58-70 : Platinum Ingot (Platinum Ore x4 + Fire Crystal) : You are going to want shittons of Platinum stuff when you're 110, so there's no reason to hold off. If platinum ore is hovering near 6k each on your server, just buy from the guild NPC and grind this stage out. Expect to invest about 10mil into platinum here. -- Entire Cursed Koenig set
70-73+ : Platinum Sheet (Platinum Ingot + Fire Crystal) : Some of the platinum you'll want at 110 is platinum sheets. Might as well convert some while they can give you skillups. -- Cursed Deichlings, Schaller, and Cuirass
Other good synths for this period: Oberon's Gold Ingot -> Oberon's Gold Sheet, Marble Nugget
73-92 : Avarite (Avarite + Wind Crystal) : Hopefully you heeded the notes and stockpiled these. Grind them out.
82-92 : Elemental Bead (Elemental Ore + Wind Crystal) : Again, stockpiled hopefully.
84-92 : Orichalcum Ingot (Orichalcum Ore x3 + Platinum Ore + Fire Crystal) : Again, stockpiled hopefully. -- You will use these in Cursed Cuirass.
87-93 : Rhodium ingots (Rhodium Ore x4 + Fire Crystal) : Keep Rhodium if you want to make rings.
At this point, you should take a break, level to 70 and do LBs, level smithing+alchemy subcrafts, and get GP items. You will want to have the Crafting HQ ring from Adoulin, torque, stall, glasses, and apron before you do the next push. I will assume you have level 70 smithing, alchemy, and all the items after this point.
With Skill+12 (including advanced support), you can Tier 1 a synth one level above you. Without Kupo shield, no one can reach Tier 2 on anything above level 91, so your HQ rate on these synths is the same as a 110+12 crafter. This is ultimately the largest secret to leveling a craft these days. There's no reason to be inferior to a 110+12 crafter above level 91, so everything you do after this point can be profit. If a lower level synth is profit and you have mats for it, feel free to keep doing it for skill as long as it isn't >11 levels below you. The listed level is the lowest level you should start attempting this synth
92 : Cursed Deichlings (Cermet Chunk + Darksteel Cuisses + Platinum Ingot + Platinum Sheet + Fire Crystal) : NPC your NQs.
92 : Bewitched Deichlings (Cursed Deichling -1 + Eschite Ore + Fire Crystal) : Hope
93 : Cursed Schuhs (Cermet Chunk x2 + Darksteel Sabtons + Platinum Ingot x2 + Fire Crystal) : Save your -1s for when you are 110 and can Tier 2 the upgrade synth.
94-100 : Snowsteel Ingot (Snowsteel Ore x4 + Fire Crystal) : Sell single ingots for RUN
95 : Cursed Handschuhs (Cermet Chunk + Darksteel Gauntlets + Platinum Ingot x2 + Fire Crystal) : Convert your -1s using Eschite Ore.
95 : Rhodium Ring (Rhodium Ingot x2 + Fire Crystal) : Can upgrade the rings to Avarite rings with synergy, I think.
96 : Cursed Schaller (Cermet Chunk + Copper Ingot + Darksteel Sheet + Gold Ingot + Platinum Chain + Platinum Sheet + Sheep Leather + Fire Crystal) : Convert your -1s using Eschite Ore.
97 : Cursed Cuirass (Cermet Chunk x3 + Darksteel Cuirass + Orichalcum Ingot + Platinum Chain + Platinum Sheet + Platinum Ingot + Fire Crystal) : Convert your -1s using Eschite Ore
At level 97, you are a high enough level to make 110+12 profit off all Voodoo Souveran pieces except Voodoo Schuhs. Consider whether you want to continue.
To break above this point, you will need to grind Cursed Koenig, Snowsteel, Hepatizon, and Ormolu ingot synths. Snowsteel and Ormolu have supply issues, so it'll mostly be Cursed and Hepatizon ingots with the latter giving better skillups.
100-110 : Hepatizon Ingot (Mythril Ore x3 + Hepatizon ore x1 + Fire Crystal) : Dump back onto the AH
104 : Nepenthe Grip [Requires Chainwork KI] (Mandrel + Rhodium Ingot + Gabbanth Horn + Fire Crystal) : Sell, make money
Various hexed synths, which you can look up