BART to SamTrans 140, hike Sweeney Ridge. Come back to the Banquianio trail, stay left to Fassler road, take the road for a bit to the trail on the left-hand side of the road, follow the trail, stay left, and head to Post Office.
Hit up Pacifica State Beach, catch some waves, then head for some local flavor. First stop at Sea Bowl for a game, then cross the street to Nick's for a view and a drink.
Next head north on the trail from Nick's, make sure to stop at Mori Point, then follow the excellent trail between Laguna Salada and the Ocean.
Catch the SamTrans 110 at Brighton and Oceana Blvd. That will take you back to the Daily City BART.