From Scottsdale, take the 101 freeway to Shea Blvd.  Take Shea Blvd. east to SR 87.  Take SR 87 north to Bush Highway (Saguaro Lake Exit), turn right and follow the signs to the lake.  Go through the entrance gate, and follow the road to the first boat ramp.
From Mesa, take US 60 to Power Rd. (north) and follow signs. Or, take SR 202
to Higley, go north on Higley to Thomas, take Thomas to Power Road, go north on Power Road which becomes Bush Highway.