One of the great things about Macs and this area in general is the Bouddi National Park. Between Macs beach and Killcare is seriously beautiful bushland with great views, serene little beaches and lots of magnificent angophora's. To the west of The Scenic Rd is also National Park and also spectacular. The walk from Macs Beach to Killcare will take you a couple of hours but is well worth it. If you want a shorter walk try starting from the information hut along Scenic Rd about half way to Killcare. Walk down the track towards Maitland Bay. About half way down is a turnoff to the south. This is a great track along the ridge to Killcare or Putty Beach. When you get to what seems the end of the line at some rocks overlooking the coast, keep going, the track continues below the rocks and even has a bit of a rope to help in the steep bits. Its almost abseiling really!
In the links below have a look at the Bouddi National Park brochure and map.