What observation method would you use to observe gross motor skills in a child?

I would watch the child as they play, run, walk, and move about a yard or play area. Might throw a ball at them to see how they catch the ball and balance themselves. I would look for right/left lateral movements and how well they move arms/legs and if they are in sync . I might set up an obstacle course to see if they can move through it and how they used their body in relationship to the objects/ space. I would make a check off sheet for myself with a scale of 1-10 for each movement and action.