When it comes to sheet masking, sometimes you get super bored within that 15 minutes. I know some people watch TV, lay down on a couch, but I like to get everything done before I leave the bathroom, so I go straight to bed without having to come back.
I always like open up my pores before a sheet mask. So I take a warm shower, allowing your pores to open, then wrap my hair with a towel. I rinse my face to remove any residues then tone it. After toning, that's when I put a sheet mask. While I wait for 15 minutes, I apply body lotion and apply hair essence. After moisturizing my body and hair, I go ahead and blow dry my hair (temperature not too hot nor too cold because you don't want to dry out your sheet mask). If I have a couple of minutes of spare time to spend, I organize my bathroom; removing any hairs that might clog the drain, dry access water on the floor or tiles, etc. Then as soon as I hit 15 minutes, I take the sheet mask off and gently dab the remaining essence thoroughly. Then, apply facial oil and a moisturizer.