One of the most suggested beaches I have read and heard about in Los Angeles is Zuma Beach. While Zuma Beach did not turn out to be my personal favorite beach in Southern California, I can see why it is a favorite among many locals.
I visited Zuma Beach on an unusually chilly day in Los Angeles, so I am assuming the beach is normally busier on a warm day. However, with less crowds and tourist attractions, Zuma Beach stays more peaceful and cleaner than other beaches. Unlike beaches with busy piers, such as Santa Monica, or beaches with popular shopping, like Manhattan Beach, Zuma Beach is for those looking for just the sand and the ocean. Zuma Beach takes up a long portion of the coast, which means there is plenty of space to lay out your towel, build sand castles, and stroll along the beach. It is also a very popular surf spot.
Zuma Beach is located right off PCH, but pretty far into Malibu. Without traffic the drive from Santa Monica Beach to Zuma Beach is about forty minutes up the coast, which is another reason why there tends to be smaller crowds. Zuma Beach does not have restaurants or food stands, so I would suggest bringing your own snacks. Another highlight for Zuma Beach is that the parking is simple and plentiful. There is a spacious paid parking lot, or, as I observed from other beachgoers, you could try to park off the side of the highway up against the gate for free.