Trophy trout like big lures, so  you should use big lures. There is still a small chance you will
catch a small fish. Once I caught a 6" rainbow trout on a 2" lure!  Trophy trout like cover, so
you should always fish near cover.  Spoons work best if you want to catch trophy trout in
rivers.  In lakes, the trout will bite best on plugs.  

Tips for trophy trout