If youre a righty then you should stand with both legs bent about shoulder width apart. Don get much wider than youre shoulders. You should stand sideways with your jab shoulder pointed foward. This adds and inch or two to your reach and lets you put more power into your right hand by swinging the hip,heel, and shoulder foward. you should keep all of your weight on that back leg while keeping the front one slightly bent, this allows you to put your weight behind the punch when stepping into your jab and thowing the right hand all while keeping your head furthest awat from the action (although sometimes you really gotta get in there).
Lastly you should point your toes in the direction youre striking.
In most cases
sideways, hands up, legs bent, weight back, toes forward