First of all, wash your new screen with a regular cleaner and let it dry. You want to be sure the surface of your screen isn’t dirty.
Now you’re ready to coat the screen with photo emulsion. From now on, try to work in a dimly lit area. You want to keep the emulsion away from light as much as possible. Follow the package instructions for adding the sensitizer to the emulsion. Now, pour some emulsion into the screen coater. Let it sit for 5 minutes or so, to let the bubbles settle.
Take a deep breath, get Zen, and coat both sides of the screen twice. With the screen coater helping you out it’s really not that difficult. Here's a video of me pretending to coat a screen. I didn't record the real thing because I didn't want to expose my screens to any light.
Once it's coated lay the screen flat to dry in a dark place and keep it there until you’re ready to expose it. Make sure the screen itself isn’t in contact with anything. Let it dry for two hours or so. The screen is now "sensitized". This means that when it is exposed to light, the emulsion will harden. The sooner you expose, the better.