I often fly from KSNA to KPSP in IFR with a Cessna 182 (SLI V64 TRM), usually after crossing the mountains before TRM VOR I receive the clearance for "visual approach RWY 31L", since the weather is almost always nice there

At the time of this clearance, I am about 15-20 miles east of the airport but still at 11.000 ft. What is the correct way to loose altitude before the final approach? Circling? Currently I am flying opposite direction with a 1000 fpm descend (poor passengers...), and then turn on final when I reach about 5000 ft.
Thanks, Thomas