Battling monsters and using Auto-Craft are two ways for your crafting to process
Crafting Guide - In the wonderful Online you can craft most of the equipment you and your Mercenaries can wear. To begin crafting a specific crafting skill you first need to either learn it from a player who has achieved "Artisan" status in that skill, or you need Tera Gold to buy the first level from an NPC.
Each time you craft an item, you will receive Experience points. Once you have enough you can learn the next level from a player or NPC.
To begin crafting you need to first open the Skills window (My Info->Skills) and select a crafting skill (See image on Right). When you click on a particular skill you will see each item that you can currently craft.
When you click on one of the items you will see what materials it needs and how many you have. Once you have the materials required to craft, you can hit the Craft button.
There are two ways for your crafting to process, by battling monsters and using Auto-Craft. Auto-Craft requires you have obtained at least 1 level using Auto-Craft (I). To use it hit the Z key. Auto-Craft works like Sitting, so you can not move whilst you Auto-Craft.
Opting for a ranged leader allows you to protect your character behind strong frontline mercenaries, but it means your avatar has lower defense and hit points.