To get around South El Monte, renting a car is the best option. The areas outside of South El Monte can be reached by car, but traffic can be heavy during peak hours. For those not driving, some spots can be accessed by public transit, such as the Metro in LA or the Metrolink in Riverside. Expect to spend roughly $$ in gas expenses if driving and anticipate travel times accordingly.
If you have more time, consider visiting the L.A. Live entertainment complex, which has a variety of dining, shopping and entertainment options. Alternatively, take a trip to Disneyland in nearby Anaheim. If you have less time, consider skipping the Riverside and Ontario locations and spending more time on the beaches.