What is said next about these false teachers comes from the pen of Peter, and it serves as a somber warning to the Christian. "And many shall follow their pernicious ways..." There are the false teachers that may appear genuine to those that are not grounded in the faith or are not of the faith, and these are headed for destruction, as Jude and Peter make clear. But not only that, among these certain men are false teachers that are good leaders, as good of leaders that are in Christendom, only their ways are evil, as have been and will be evident. While following God and Godly leadership leads to a victorious life, following these men is a "pernicious" way (see contrasts in Psalm 1 and throughout Proverbs (i.e. 19:21, 20:18)). In other words, those who are deceived by these deceivers are headed for the same destruction that they are! Not only that, but the Bible says that many will be.
The application: Since this matter is already settled, there are two things the Christian can do. First, watch your back. Be cognizant of these ungodly men. Earnestly contend for the faith. "Light always shines brighter in a darker place." -Max Fernandez. Second, be a part of damage control. Contend for the faith by attempting to win ungodly men to Christ. His judgment is certain, meaning we have a finite amount of time before He comes and it's too late to do anything (I Thes. 5:2).