Equip a tool in your main hand, then with hold Left click on an item in your inventory, select the skills icon (the face), then click repair.
Even if you're successful, the max condition of your weapon will decrease. Read the wiki link for more detail
http://www.fonline-reloaded.net/wiki/index.php?title=Repair
You don't actually
need a tool in your hand, but it does help (as it gives a bonus to your repair skill; super tool kit gives an even bigger bonus).
If the repairing goes "perfectly", the item you repaired will not lose maximum condition %.
When you're using a tool, it will have a chance to break while using it. When you're repairing a vehicle, you
will need a tool in your hand.
Topic: how do you use the repair skill to repair items (Read 1563 times)