There are many interesting and diverse pottery decorating techniques involving the use of slips. Effects range from very linear to very textural, and from very fluid to quite hard-edged.
Slip tailing is one of the most widely known and used methods of decorating with slip. Slip trailing delivers a stream of slip to damp or leather-hard clay through some type of dispenser.
This dispenser can be a large-bore syringe such as a baster, or a bottle with a nozzle such as used for condiments or glue. In either case, the dispenser's opening must be wide enough so that it won't easily clog. In addition, the slip used consist of fairly fine particles also, again in order to reduce clogging.