The serve is like a overhead throw of a baseball or a football. I recommend beginners to serve with a "Semi-Western" grip to build strength. Until strength is built, you should switch to a "Continenta" grip.
Here is a picture of a overhead toss. All throws have something in common. Here are the steps.
The racket motion is the exact same as this throw. Adding spin on the serve is the same as putting spin on a overhead ball toss.
For your stance, you should have your left foot point to the right net post, and you should have your right foot parallel to the white line.