This is a guide on economical leatherworking training.
As this is intended to save you money, buy only the materials you are sure you will need. If you run out then buy more. It is always more cost-effective to gather your own materials rather than buying them. Avoid having extras, but if you do, try to sell them back on the Auction House.
Alternate steps are marked in green. Steps in which there are more than one option are marked in blue. If you consider these options, obtain all the standard materials but disregard the total numbers in favor of the option totals.
Apprentice Leatherworking allows 75 maximum skill, requires level 5.
If three Ruined Leather Scraps are cheaper than one Light Leather, it's actually a good idea to convert as many scraps as possible to light leather, which brings the skill up to 34, and start creating Handstitched Leather Cloaks only then.
Journeyman Leatherworking allows 150 maximum skill, requires level 10 and 50 skill.
Note in the following table that the [Dark Leather Belt] requires the previously-crafted [Fine Leather Belt] and [Cured Medium Hide]. (i.e. don't make the mistake of vendoring these.)
Expert Leatherworking allows 225 maximum skill, requires level 20 and 125 skill.
Artisan Leatherworking allows 300 maximum skill, requires level 35 and 200 skill.
Master Leatherworking allows 375 maximum skill, requires level 50 and 275 skill.
Grand Master Leatherworking
Grand Master Leatherworking allows 450 maximum skill, requires level 65 and 350 skill.
Worry not about this seemingly hard material, you can exchange this
1 [Arctic Fur] can be bought for 10 [Heavy Borean Leather]
6 [Borean Leather] can be tailored into [Heavy Borean Leather]
Total 60 [Borean Leather] for each Artic Fur