From Los Angeles:

Head east on Interstate 10
In the Upland area, look for Highway 83 north to Mt. Baldy

From San Bernardino:

Take Interstate 215 north to Interstate 15
Head south on I-15 to Highway 66
Head west on Highway 66 to Upland
In Upland, look for Highway 83 (Mountain Ave.).
Head north to Mt. Baldy

From San Diego:

Take Interstate 15 north to Highway 66
Head west on Highway 66 to Upland
In Upland, look for Highway 83 (Mountain Ave.).
Head north to Mt. Baldy