1) To level RuneCrafting, open your Magic Book and look for the Skillers teleport spell.
2) Teleport to Skillers and buy a pickaxe.
3) Next to the rock in the Skiller Zone there is a portal, go inside this portal to get to the Rune Essence mine.
4) There are 4 rocks, mine them for rune essence.
5) When you want to turn those essence into RUNES, go to the portal by the 4 rocks, it will take you to the Abyss where there are several areas* you can runecraft at.
6) At level 1, go into the Air altar and click on the center altar, the essence will then convert into Air Runes and you will be rewarded EXP.
7) The Best EXP Rewarded is for AIR Runes, and you will see why in the chart below.

*-There are a few areas in which you cannot go to runecraft, or that do not work. A) Blood Rift cannot be entered. B) Soul Rift cannot be entered. C) Mind Altar does NOT work.

EXP RATE
At Normal EXP Rate**:
Rune Type - Amount of EXP per 28 essence
Air - 1,680,000
Water - 1,344,000
Earth - 1,008,000
Death - 840,000
Fire - 840,000
Chaos - 873,600
Cosmic - 728,000
Body - 756,000
Nature - 1,344,000
Law - 784,000

**For a Higher Donator Level you will receive a higher EXP rate.
EXP Rate for donator level is:
Level - XP Increase
10 - 2x
25 - 2.5x
50 - 3x
75 - 3.5x
100 - 4x
150 - 5x

Meaning at 150 Donator Level (GOD Status) you would get that exp *5.
At GOD EXP Rate:
Rune Type - Amount of EXP per 28 essence
Air - 8,400,000
Water - 6,720,000
Earth - 5,040,000
Death - 4,200,000
Fire - 4,200,000
Chaos - 4,368,000
Cosmic - 3,640,000
Body - 3,780,000
Nature - 6,720,000
Law - 3,920,000