(click on images to view GIF's)

Wavedashing is an advanced technique used in Super Smash Bros Melee for the Nintendo GameCube that takes advantage of the game's physics engine and enables players to move horizontally while still being able to complete actions as if they were standing still. This is a very useful skill to have because it opens up a lot of options for approaching and retreating from the enemy fighter as well as being the only way to move backwards while still facing forward. Also, when a player wavedashes backwards off of an edge, they will tumble off the stage but immediately grab onto the edge, providing a very quick way to edge-hog.

What you need:

A Nintendo GameCube with a copy of Super Smash Bros Melee
A high quality Controller (knock-off brand controllers are generally not as responsive and it will be much more difficult to achieve the correct timing needed for this technique)
Time and dedication to master this advanced technique

Step 1: Input a Jump Command

While your character is on the ground, start a jump.

You can do this with either Y / X / control stick up.

However using Y / X is usually the most natural feeling since you will need to use the control stick for the next part.

Step 2: Perform a Down-angled Air Dodge

Immediately after your jump animation starts, perform an air dodge that is angled diagonally towards the ground and the direction you want to slide.

This is done by pressing L and holding the control stick in the desired direction (this could be in the opposite direction as your character's momentum if you're nimble enough with the control stick).

When timed correctly, your character will barely leave the ground (if at all), and simply slide horizontally in the chosen direction, as you can see Luigi doing at half speed in the above GIF.

Step 3: Refine Your Technique

Each character has a different wavedash length that is dependent upon their traction to the stage (with Luigi's wavedash being the longest and Peach's being the shortest). Also some characters have a slower startup to their jump animation (Bowser, for example) so this will affect the timing of when you should air dodCge.

Practicing:

When practicing wavedashing, it is best to use a "slippery" character with a longer wavedash to get a feel for the timing such as Luigi, Mewtwo, or Marth.

Uses:

Once you get the hang of it, you can start stringing wave dashes together one after another, allowing you to move across the stage faster than dashing and with the additional utility of being able to very quickly change directions.

You can use this skill to quickly close distances with an enemy and still keep your offensive and defensive options open, since your character is technically standing still allowing for things like a sliding forward smash, a sliding standing grab, or just shielding out of the wavedash. This opens up many different options for change-ups and mind games with your opponent as they will have to guess what you're going to do each time.

As mentioned in the intro, wavedashing is also one of the quickest way to edge-hog the stage. Simply wavedash backwards over the edge of the stage and your character will be put into the tumbling state, but since you're right next to and facing the edge, your character will automatically grab onto the edge, providing a good edge-hogging option against your opponent.

Caution:

While wavedashing is a valuable skill to have, when performed incorrectly or in the wrong circumstances it can give your opponent a golden opportunity to attack or even cause you to self-destruct.

Mistiming your wavedash: If you air dodge too late after your jump, your character will be fully in the air when you do your air dodge and will perform a normal air dodge, leaving your character falling the rest of the way to the ground in the vulnerable "helpless" state, giving your opponent a perfect moment to set up a combo or finish you with a smash attack.

Wavedashing too close to the edge: While wavedashing to edge-hog close to the edge of the stage, if you mess up the timing on your wavedash it is possible for your character to air dodge too far away from the stage and miss the sweet-spot for an edge grab and cause you to self-destruct!