What your talking about is your 2nd safty. On the right side you have your regualr type safty, and the part your talking about works like this.

1st make sure the gun is unloaded
2nd pull back that hammer, you should hear a "CLICK"
3rd spin the end so that the red is showing, the red means it ready to fire
but with a knight you have to have the side safty in the red, now shes 100% ready to fire
Also call Knight, tell them the model and you need a owners manual

KNIGHT 641.856.2626