Metro: Hundreds of extra buses are being provided with shorter turn-around time between them. Numerous Line & Main Corridor routes as well as Red, Purple, Orange rail lines will be free of charge. Metro has also prepared for Saturday night's LA Galaxy vs Real Madrid soccer match at LA Coliseum by adding more buses on site.
Metrolink: Additional trains have been added to both the Antelope Valley and the Ventura County lines. Buy a $10 weekend pass and have access to all lines. Connections from train to rail or bus are complimentary so Metro suggests that "after you purchased your Weekend Pass and took Metrolink from Irvine to downtown LA, you can board the subway at Union Station and ride all the way to Hollywood and Highland for free!"
Amtrak: 50% discount for Pacific Surfliner® coach passengers travelling between LAX and BUR airports. This means you can traverse the city for $3 per adult roundtrip ticket.
Braving The Pavement: The LA Times reports on all alternative canyon routes and HuffPost Comedy entertains us with less commonly thought of alternatives.