In order to get medals in your Medal Gallery, perform the following tasks:

Effect - Code

Medal #1 - Get the "HSG Star" Rank
Medal #10 - Sink the ball in with Super Backspin on any course
Medal #11 - Sink the ball in with a Spiral Ball on any course
Medal #12 - Sink the ball with a 60-Yard Putt on any course
Medal #2 - Get the Platinum Challenge Rank Level
Medal #3 - Unlock all the characters in the game
Medal #4 - Get Maximum Loyalty Hearts with all characters
Medal #5 - Complete Putting Challenge and Challenge Mode
Medal #6 - Sink the ball in with a Hole-In-One on any course
Medal #7 - Sink the ball in with a Double Eagle on a Par-5 Course
Medal #8 - Sink the ball in by hitting the Pin on any course
Medal #9 - Sink the ball in with Super Topspin on any course