The quest to gain the Crafting skill begins at Level 31 in Sunstream City.
To Craft press "O".
To Learn new recipes simply double click them while they are in your bag, it will say using item, then it will add them to your crafting list.
The amount of skill points need to reach the next level are:
Lv 1 -> 2: 80 (Each Lvl 1 item is worth 12 exp) 7 items (6.6) Lv 2 -> 3: 600 (Each lvl 2 item is worth 24 exp) 25 items Lv 3 -> 4: 3600 (Each lvl 3 item is worth 48 exp) 75 items Lv 4 -> 5: 14000 (Each lvl 4 item is worth 96 exp) 146 items (145.8) Lv 5 -> 6: 41000 (Each lvl 5 item is worth 192 exp) 214 items (213.5) Lv 6 -> 7: 110000 (Each lvl 6 item is worth 384 exp) 287 items (286.5) Lv 7 -> 8: 300000 (Each lvl 7 item is worth 768 exp) 391 items (290.6) Lv 8 -> 9: 590000 (Each lvl 8 item is worth 1536 exp) 385 items (384.1) Lv 9 -> 10: 1200000 (Each lvl 9 item is worth 3072 exp) 391 items (390.6)