Basically, they act like permanent-until-discharged, placeable spell effects.
You need the Inscribe Rune feat (prereq: Int 13+, appropriate craft skill, divine spellcaster 3+), which basically describes what rune magic is:
You can cast any divine spell you have prepared as a rune. The caster must have prepared the spell to be scribed and must provide any material components or focuses (foci?) the spell requires. If casting the spell would reduce the caster's XP total, je pays the cost upon beginning the rune in addition to the XP cost for making the rune itself. Likewise, material components are consumed when he begins writing, but focuses are not.
A single object of Medium-size or smaller can hold only one rune. Larger objects can hold one rune per 25 square feet (an area of 5 feet square) of surface area. Runes cannot be placed on craetures. The rune has a base price of the spell level X caster level X 100gp (a 0-level counts as 1/2 level). You must spend 1/25 of its base price in XP and use up raw materials costing half its base price. A rune's market value equals its base price
Note: i didn't proofread. And I won't.
Inscribing a rune takes 10 minutes plus the casting time of the spell included.
Inscribing a rune requires a Craft check against a DC of 20 + the level of the spell used.
Hope that helps
Maitre D
