While playing with a character that uses a lightsaber, press X to attack, but do not immediately press it again. Wait until the slash/attack stops, then quickly press X as soon as it stops. If done correctly, the next slash/attack will feature a "sparkle" effect on the lightsaber blade. Do the same thing for a special finishing attack. Additionally, immediately after the first or second slash/attack, press Jump for a special jump that puts you behind your target. Press X while in the air for a small area of effect attack.