To do a Sailor Scouts Power (ex. Mercury bubbles), hold the L button on the top and any other button (ex.L+x=a move) Try diffrent combinations to look at more cool moves.
To do a Super Sailor Power, looks at your character. If your heart crystal is glowing, quickly press R and L and the same time.
View Animations
At the options screen (the third one down from the top if you don't speak japanese ^_^) use the following buttons to access the animations: Left shift, X, Y, Z, Right shift. You will see a new menu pop up, enter this menu to view the sailor scouts' henshin sequences.