The easiest way to exorcise a yurei is to help it fulfill its purpose. When the reason for the strong emotion binding the spirit to Earth is gone, the yurei is satisfied and can move on. Traditionally, this is accomplished by family members enacting revenge upon the yurei’s slayer, or when the ghost consummates its passion/love with its intended lover, or when its remains are discovered and given a proper burial with all rites performed.
The emotions of the onryo are particularly strong, and they are the least likely to be pacified by these methods.
On occasion, Buddhist priests and mountain ascetics were hired to perform services on those whose unusual or unfortunate deaths could result in their transition into a vengeful ghost, a practice similar to exorcism. Sometimes these ghosts would be deified in order to placate their spirits.
Like many monsters of Japanese folklore, malicious yurei are repelled by ofuda (???), holy Shinto writings containing the name of a kami. The ofuda must generally be placed on the yurei’s forehead to banish the spirit, although they can be attached to a house’s entry ways to prevent the yurei from entering.