I'm no instructor but have stumbled onto a little routine that helps me stand the right distance from the ball. For my height and with the clubs I use the distance from the ball equals one club length. To measure this, when I set up, I lay the club head on the ground behind the ball and then bend at the waist until the handle is on or near the ground. I then set the backs of my heels to end of the shaft and voila that's how far away I stand.

I found this first after hitting a couple of good drives at the range & then discovered it held true throughout the whole range of clubs. The shorter the club, the closer I am to the ball. It's been a big help for me to get the "feel" of my setup and to generate more confidence going into my swing. Hope this helps.