your takeaway angle will be determined by your body mechanics. In general the driver takeway must be flat (absolutely NOT upright).

If you are slicing with this method it is because you are outside of the swing plane. The reason many do this is that they are focusing on both a flat takeaway AND taking the clubhead back on the target line. The problem is that you must flair your right elbow out to accomplish both. THIS IS WRONG.

A square clubhead does not mean that it must travel squarely on the target line. It must travel sqaurely on the swingplane. Focus on keeping your right elbow tighter to your body, and your left elbow closer to your right elbow. This avoids the dreaded "chicken wing".