From the EAST via Long Island Expressway:

Exit Long Island Expressway, I-495 via ramp at sign reading
Exit 36 to Searingtown Rd / Shelter Rock Rd
Bear left on N Service Rd
Turn right on Shelter Rock Rd
Turn left on Northern Blvd, RT-25A and go West to P. S. Honda

From the EAST via Northern State Parkway:

Exit Northern State Pkwy via ramp at sign reading 
Exit 27 Shelter Rock Rd to Manhasset / Searingtown
Turn right on Shelter Rock Rd
Turn left on Northern Blvd, RT-25A and go West to P. S. Honda

From the WEST via Northern State Parkway:

Exit Northern State Pkwy via ramp at sign reading
Exit 27N Shelter Rock Rd North to Manhasset
Bear right on Shelter Rock Rd and go Northwest for 1.9 miles
Turn left on Northern Blvd, RT-25A and go West to P. S. Honda

From the WEST via Long Island Expressway: