1.Go To Private Match
2.Click Change Game Mode And Put SnD
3.Edit Game Options
4.Save To Your File Share
5.Load The Saved File.
6.Go To Edit Game Options
7.Save And Replace The File.
8.Go To Combat Training
9.Go To Switch Lobbies And Hover Over Private Match [Don't Click It Just Hit B]
10.Go To My Playercard
11.Go To File Share
12.Then Go To The File You Saved And Load The Game [Mash The A Button]
13.Then It Will Load As Combat Training Search And Destroy!~!~!

If This Helped Click The Thanks Button I Know Their Were A Lot Of Tutorials
Just Wanted To Add My Own :] So Don't Say [o.o Posted already]