During dry fire, do you index your finger or put it on the trigger?

Hey guys,​I'm relatively new to guns. When I am at the range, generally holding the gun, etc I will have my "index" my finger and obviously keep it off the trigger until I am ready to shoot.​When I have practice dry firing from my holster, I have always immediately put my finger on trigger as I am raising the gun to my target. Recently, I was wondering if I should get in the habit of keeping it indexed until I am on target.​I feel like this would have safety advantages, but at the same time, if I need to shoot immediately it will slow me down.​What are your thoughts and what do you guys do? via /r/CCW http://bit.ly/2WGRbR2