Open up each of the two containers one at a time. Put non-latex gloves on if preferred. If not, it’s only silicone. Divide the goo in the containers in two (one for each ear).
Take one of each color of goo and knead them together. Keep kneading for about 30-40 seconds until it’s all one color, and make a nice round ball.
Place the ball of goo into the ear. Gently massage it into the ear until it fills the ear as shown in the picture. Don’t push it too far into the ear canal but enough to help it stay in place. Smooth it over.
Take the in-ear monitor (this is where it helps to have the mirror, assistant, phone/iPad combo, etc.) and gently press it into the goo where you’d normally have your in-ear monitor in your ear. Don’t push it in too far. Only get it in far enough that the sound canal is embedded in the silicone, not pushed through. Do the other ear the same way.
Now sit for about 10-20 minutes while the silicone cures. During this time, try not to move around too much and do not talk. If you’re a singer then keep your mouth slightly open and just find something to wipe the drool from your chin—otherwise you’ll look like a St. Bernard that’s just come in from a long hike!
These 10 minutes will seem like an eternity since as the silicone cures it sounds like a Rice Krispies convention is going on in your ears!