Choose a bike that you don't mind getting ruined. Even when you're careful, your bike's drivetrain can go through torture when riding in the snow. Put fenders on your bike so snow won't be thrown up onto your butt. You might also want to install a bike rack to keep the snow away from you. Nothing is worse than having a wet butt while riding in the snow.
Check out your road conditions. Determine whether you'll be riding on water, ice or snow. This helps you decide what kind of tires you should use for your ride.
Install thicker tires on your bike for the inclement conditions. Thicker tires grab the snow better and do not cause you to slide as easily. Consider putting chains on your bike if the roads are particularly icy. The chains help you gain traction so you don't slide.
Lower your tire pressure when riding an electric bike in the snow. Lowering your tire pressure by about 10 pounds can help you obtain better traction.
Prepare your brakes and chain. Lubricate your chain well so it moves freely and doesn't lock up. Disk brakes are the best type of brakes for road bikes in the snow. These brakes are expensive, but worth it, if you're planning on doing a substantial amount of road biking in the snow. If you have pad brakes, try not to use steel chrome rims. These types of rims can cause problems when braking during wet weather.
Ride slowly when road biking in the snow. If you're not in a race, take your time to get to where you're headed safely. Be sure to pay attention to what you're doing. This is not the time to allow your mind to wander.