Coming from Honolulu, take the H-1 freeway east to Highway 72 (Kalanianaole Highway). Stay on Highway 72 and pass Hanauma Bay and Sandy Beach on your right and the Hawaii Kai Golf Course on your left. Soon after passing the golf course you'll see a parking lot on your right. That is the trailhead for the popular route I mentioned earlier. Instead, keep going until you see another parking lot that offers a lofty view of Makapu'u Beach and the windward coast. Park there.
Coming from the windward side, take Highway 72 (Kalanianaole Highway) heading southeast, passing the towns of Kailua and Waimanalo. Pass Sea Life Park on the right, and then Makapu'u Beach on the left. As you are passing Makapu'u Beach the road will climb a bit up to a parking lot on the left. Park there.
From the parking lot, jump the stone wall and follow a trail on dry and rocky terrain to a wooden utility pole far uphill. Trails come from every direction, and all lead to the same place, so take your pick. After reaching the utility pole you'll see the obvious way down heading to a road to the lighthouse overlook. Soak in the views, snap picks, have a picnic: when you're done, turn around, and hike back the same way you hiked in.