The Potatoe Banishing
If you know the identity of the spirit, having something that belongs or is otherwise tethered to them you may perform the potato banishing. Take a potato, having skin and preferably unwashed and halve it. Having hollowed out a small section, leaving fairly thick walls; place an object belonging to the deceased, or in the case of some other entity an object of desire, inside the hollowed out space. Then, using two long nails or pins, reseal the potato. Take it to the cemetery where they are buried or some other appropriate place and leave it. The spirit should be bound there until it is released to it's path.
There is also an old trick of offering potatoes to a spirit before sun-down and then moving them to some other place that it may follow and become lost. This is not an attempt to insult the inteligence of a spirit but rather an act of sympathetic magickal drama to create an atmosphere of confusion.