There is a standard draft plan when it comes to selecting defense/special teams for your fantasy league. It is pretty simple: Wait until the last two to three rounds, near the end, my friend. 

That is a pretty good rule, and it has worked for quite a long time. The reasoning is fairly simple: 

1. The disparity between a really good defense and the best of what is normally on the waiver wire is small compared to other positions. 

2. DST performance can vary wildly from season to season, so it can be hard to predict which will be the top units.