Usually its a completly waste of time crafting most of the itens.
Altought it gives a good bonus, it takes too much time to craft. You probably will run out of knife very quickly so it doesnt worth crafting.
Stuff like Armor, shoes, hat worths the effort, since you keep for a longer time.
To level your Jobs and craft itens, you must complete some quests depending on the job.
Check the in-game guide.
Be the change you wanna see to the world.