You must first purchase the necessary texts to learn how to inscribe. Then you must buy supplies. Scribing pens enable you to write the runes onto equipment and slots are where the runes are placed on the equipment. These things can be found on the items pages. You may only inscript equipment. Each piece of equipment may only have one level 1 rune and one level 2 rune inscribed into it. Weapons and gloves may also have a level 3 rune. Once inscribed you change the item name. You may also inscribe other people's equipment as long as you are in the same location as them. If you are going to charge for inscriptions you must due so via the auction house so it can be accounted for.

To inscribe a rune into an item it takes 1 week and holds up a building slot.

For example:

Weighted Gloves of Fire ( level 1 rune)

or

Weighted Gloves of Fire and Rage (level 1 rune, level 2 rune)

or

Scorching Weighted Gloevs of Fire and Rage (level 1, 2, and 3 runes)

Must know special ability Inscription 1

Fire - Increases training by +3 strength per week.
Wind - Increases training by + 3 speed.
Water - Increases training by +3 vitality
Earth - Increases training by +3 toughness
Spirit - Increases training by +3 stamina

*note* If followed by a level 2 rune and item would say Super Weighted Clothing of Fire and Rage. The name of the level 2 rune comes second.

Must know special ability Inscription 2

Please note, you can only have one of each level 2 rune equipped.

Rage - +200 strength in battle.
Grace - +250 speed in battle.
Health - +200 vitality in battle.
Consitution - +200 toughness in battle.
Enduance - +200 stamina in battle.
Knowledge - +20 intelligence
Willpower - +20 determination
Personality - +20 charisma
Combat - +10 exp to battles and +5 exp to spars.
Energy - Ki attacks do 1% more damage
Might - Phyiscal attacks do 1% more damage.
Training - All training adds an extra +1 to stats.
Technique - +1 SP to master training per week.
Restoration - Increases the effects of healing items and the ability Heal by 5%.
Fortune - Increase zeni from side jobs by 50.

Must know special ability Inscription 3

These runes may be inscribed on weapons and gloves. They have a 10% chance of hitting. Effects last 4 actions.

Scorching - Reduces toughness by 15%
Freezing- 10% chance to cause your opponent to lose 1 action on their next turn.
Toxic - Increases ki drain by +25% (i.e. a move that would take 20% ki now takes 25%)
Clouding - Lowers all traits by 40%
Shadow - Increases damage done to Lawful Good by 5%.
Holy - Increases damage done to Chaotic Evil by 5%.
Debilitating - Decreases strength by 15%.
Energy Stealing - Steals 1% ki.
Grooved - Increases prepared weapon technique slots by 2.