Forcing is any act of tulpamancy. Many people consider forcing a meditation-style activity, projecting oneself into a wonderland to develop or interact with a tulpa; forcing can be any active interaction with a tulpa, with or without the use of a wonderland.
Passive Forcing is any interaction with a tulpa as a secondary (passive) activity. One method of passive forcing is narration, which is simply narrating any subject matter to your tulpa for the sake of strengthening the subconscious understanding of their existence.
Active Forcing is any interaction with a tulpa as a primary activity.