Slicing is a shot that is the bane of huge numbers of golfers.  Maybe you too.

Suggestions for fixing a slice are far more numerous than the number of causes for your slice.  There is, in fact, only one reason you slice; the clubface is open to the path of the club at impact.

This could mean the path is correct and the clubface is open (aiming right for a right handed golfer), the clubface is reasonably square and the path is moving to the left (outside-in), or a combination of the two.

The varying combinations of path and clubface determine the initial direction of the shot and whether it stays on that line or curves.

Understanding this much helps you understand that swinging to the left will only exaggerate your slice, rather than fixing, or allowing for it.

While other things such as the point of contact on the clubface also influence direction, they are minor compared to clubface and path.

Your swing path being outside-in is the major contributor to slicing.  To check your swing path through impact, have a look at the direction your divot is pointed.  If it is aiming left of your target, then your swing path was outside-in.  The longer your shot, the more the slice effect is exaggerated.