Not to overwhelm you, but there are many other better methods of meditation than NSDR. First, clean and protect your aura with any of the following. (You could also vibrate ALGIZ).
Protecting Your Aura:
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Protection.html
Returning Curses 1 & 2:
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Returning_Curses.html
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Returning_Curses2.html
ALGIZ:
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Odin.html#ALGIZ
From there, if you're looking for deep relaxation, use these methods instead:
Blue Light:
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Blue_Light_Meditation.html
Beautiful Meditation:
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Satans_Meditation.html
Or even vibrate SATANAMA or SATANAS for 10 minutes and that'll place you in an even more protected relaxation. You can then Void with better success without being as prone to attacks or negative thoughts.