Here,
739 Mew2king edguards, watch bits and pieces for fun and to pick up new things. I'm quite fond of run -> bair as the fastest way to grab ledge or face away offstage to set up for a dair or bair (you can cover a lot of space like this), side-b into a charging spacie up-b to fair or reverse dolphin slash, or a well timed tipper on the ledge. Learn to ledgehop dair spacie recovery consistently, it helps a lot.
Also, an important thing in edge guarding is manipulating where you opponent will go and punishing the choice they make. If you take ledge against a ganon or falcon (as seen early in the video) they are forced to land on stage and take your punish or be ledgehogged. Similarly, if you take ledge against a spacie, they will have to land onstage. Figure out what they will do given their position (if they are below, they will up-b, if they are slightly above the stage, they could side-b) and be ready to counter that. If you space yourself to tipper the ledge when they try to up-b, you cover their option of sweet spotting, so they'll go above in an attempt to avoid you or challenge your timing by sweetspotting anyway. Be prepared to cover both options.