First the lid needs to be placed on the jar and screwed tightly closed. Drill hole through top , closer to sides than middle .
This is what the grommets package actually looks like , they are located with the hard to find items @ Lowe's 2 in a package for $1.04
Push rubber grommets through the hole you drilled . Then you're ready to place your straw through the grommets :)
wash it out with warm soap water and it's ready to use :)
Jar $1 , 2 grommets $1.04 ,Straws 10 pack $1, TOTAL COST $1.62 each :) Much cheaper than the spill proof tumblers selling for $12.99 at local retailers ! GOOD LUCK !!!!