Park in the neighborhood at the north side of Berendo St and Cromwell Avenue and climb the stairs up to Los Feliz. Follow the instructions in the link so you don't get lost.
We highly recommend the cafe at the end of the pier for lunch. No reservation needed, just walk down to the end and get in line to order. If you are there a little later in the day the restaurant is great also. Make a reservation to avoid long lines. Street parking is free in Malibu if you can find a spot.
If you are coming from afar, Disneyland might be something you want to consider.
Universal is also another popular site for many.
If you are making a trip of it Vegas is very doable also. I recommend flying from LAX. It is not expensive and the drive is long.
If you do Las Vegas you definitely need to look at a helicopter or day trip to the Gran Canyon.
If you are more interested in extending your stay so you can ride the PCH then make sure to look at stops like Big Sur along the way.
Just walk around the boardwalk and take in all the people. Definitely stand and watch the skaters at the skate park.
Browse the shops, see the Ferris wheel on the pier, and walk on the beach.
Strongly recommend Hermosa or Manhattan Beach if you are looking to sit out for the day. Walk along the strand and gaze at all the unbelievable houses.
If you venture south to San Diego then the San Diego Zoo is a must.
If you are a soccer fanatic like we are, check the schedules for LAFC and Angel City at BMO Stadium.
Never seen a Baseball game? Go out to Dodgers stadium and watch the Dodgers play. Be prepared for bad traffic, expensive hot dogs, and lots of people though.
Definitely check the schedule at the Hollywood Bowl. They host concerts and movies with a live orchestra. Pretty cool place for either with the Hollywood sign in the background.