Walking
Making a forward or backward input while being in a neutral state. While walking, you can still executive actions as though you were standing still. The initial frames of walking are often faster and travel a farther distance than the remaining animation of the walk. The initial and prolonged walk speed as well as the distance traveled during the initial walk animation differ from character to character.
Crouching
Making a down input while being in a neutral state. After a couple initial frames of animation the character will reach a crouching state where many high attacks and throws will whiff the character as this lowers their hurtbox lower than standing. Often times it is faster to reach a crouching state or even lower by inputting a crouching attack (such as Down 1) for a more immediate lowered hurtbox at the cost of recovery frames.
Jumping
Making an Back Up, Up or Forward Up input while being in a neutral state. While jumping, you have access to Jump 1, Jump 2 and Jump 3/4. You are unable to block until you land on the ground and your jump kick (Jump 3/4) can only be cancelled on hit. Jump 1 and Jump 2 can be cancelled into another attack on block or hit but cannot be cancelled if they are flawless blocked. A common strategy is to buffer an input to cancel jump kick into another attack that only comes out on hit and to guarantee pressure on your opponent by making them block your Jump 1 or Jump 2 first before cancelling into something else as you land.