Great link but not as easy as it looks that glue part is very tricky. if you get the smallest dab of glue lower than the headof the light your screwed might as well throw it out it wont work. What I did was everything except the glue on the inside the nock. The only difference is after shooting you have to remove the nock to turn off. For practice why bother turning it off? In a hunting situation you want it to stay on anyway. These suckers are much brighter than lumenocks and are much more durable. Also try local tackle shops I found mine there saved the shipping which kills you with cabelas paid $2.85. Good luck