i had the 3M-badge whithout playing for 5 hours. i just used the golden gun whenever the turtle began to slow down (after 3 or 4 bounces). the rocket was used quite after the start. with this tactic, the 3M feet were quite easy to reach. i even had 3.88M ;)
 "Tic Tac Toe 4x4"){kind=icon}
 "Toss the Turtle"){kind=icon}
 "GeoSketch"){kind=icon}