Either A:
Or B:
This is of course assuming you're coming from the city north along Freeport Road. Also of note, if you were to take (A), you could use the parallel roads of Werner Camp and Denny Camp to bypass roughly the stretch of Freeport from Route 910 to just past the turnpike. Pretty much bypassing the main business stretch of Harmar on a much much quieter road.
Also, on your final approach to the mall, it might be a better idea to keep going along Tawney Run Road up to Butler-Logan Road to cross Route 28 and take a much less trafficked entrance to the Mills. The main road, Pittsburgh Mills Blvd., is several lanes wide and pretty busy.