For a Runeword to work, you need to combine two halves into a single item. This means it needs to be an item that can have two sockets, a two-handed weapon, pants, chest, or helm. There are ritual ...

A single Rune on its own does nothing, but installing two Runes onto the same item will create a Runeword. These Runewords ...

To use a Runeword, you’ll need to have a piece of equipment with two empty sockets in it (one socket to hold each half of the Runeword), one Rune of Ritual, and one Rune of Invocation.