Have you done any research or searching about this before posting this? Do a search for DredgeATog on these boards and TMD, and you'll find plenty of ideas. As an example, here's some discussion, and one of the last versions I worked on can be found here.

Crap like Bayou, Nimble Mongoose, Academy Ruins, Crime/Punishment, and Extirpate are probably all a waste of time, and dilute the strengths of the deck. Counter some stuff, draw and dredge tons of cards quickly, and kill your opponent. Tarmogoyf is most likely worth putting in at this point as an alternative kill, in light of random crap running around like Extirpate and Haunting Echoes.

A well built Psychatog deck can play the Aggro/Control/Combo parts effectively when necessary.