Though the idea of freeline is somewhat cones from skateboarding, the pumping technique is significantly different. Unlike skateboarding, you are pushing against the ground through your skates as skate rollers do. You can do the pumping both ways, so it doesn't matter which of your foot is forward. Just keep one foot pushing in while the other feet are pushing out. Make sure your pumps are symmetrical, and you have your knees slightly bent for mobility.