deconstruct every single piece of everything you get while you are still in the lower levels (whites, greens, blues, purples, everything), and you will have blacksmithing, clothing (anything hide/leather/cloth, etc), and woodworking up to 50 in literally no time.

Lot's of players sell 'intricate' items in guild traders - while you have to buy them for gold you will level up very quickly by deconstructing top-level intricate gear. If you join a friendly guild many players will give you top level intricate gear for free.

Do a crafting writ every day - they also reward crafting experience. It's not very fast but it rewards you with materials as well. At the very least get 'certified' do the first quest as that gives some experience for basically nothing.

A frustrating and expensive way to power-level is to make items and then deconstruct them. HOWEVER you get less inspiration from deconstructing something you crafted yourself, so a better way is to partner up with someone else (or even another of your own characters). Both of the characters make a load of items and then swap them over and deconstruct each others.

Learning motifs provides a tiny amount of crafting XP. When you complete research you get some too.

Just a little tip - I find clothing is the quickest of the equipment crafts to level up, so if you are going all out learning crafts you may as well get a head start on the others too.