Alright, first off, thanks for the reply!
He's currently having trouble moving and edgeguarding, with neutral actually being a decent point for him bare in mind he doesn't just run in and do ****.
Okay, so he is at least at the point of not being too crazy that he kills himself, that's hard to turn around psychologically. If he has trouble moving around, he needs to start practicing the basics. You already know of the basic movement techniques of dash-dancing and wavedashing/wavelanding. Falcon has the longest dash-dance in the game and a decent wavedash and waveland. My advice is to practice dash-dancing first. Focus first on using the furthest length of the dash and then dash right back, then focus on shorter lengths. Then combine the two in order to move across the stages without coming out of the dash-dance. To get a clearer idea of the length, practice it on all of the stages main platforms since the dash-dance length covers each one. After that, practice the furthest wavedash and waveland lengths to gain access to more spacing options since they can be combined with dash-dancing and can increase landing options, etc.
Once he is comfortable with his movement, then he can start applying it with aerials and grabs to space you out or start a punish.
In terms of edgeguarding, there are different ways to edgeguard with Falcon. On fast-fallers, if a spacie is close enough to the stage, Falcon can catch them with an offstage soft knee to an Uair followup to ultimately knock them away. After that, Up B back to the ledge. Another thing that Falcon needs to use for edguarding is ledgehop aerials. Since Falcon has his own invincible ledge-stalls, he can use them to keep control of the ledge and stay safe if done correctly. This forces the opponents to go on stage and since most good characters have significant landing lag after the recovery, Falcon can ledgehop and jump back onto the stage while using an aerial. If the opponent lands on a platform, use the Uair in order to clip the opponent with the toes and then punish off of the hit. If the opponent lands right in front of you on the stage, come onto the stage with the knee (try to get the reverse hitbox in order to guarantee that the opponent will be sent right back off the stage, if you don't, the opponent has the chance to live longer). There is of course the ledge hop Bair to hit the offstage opponents away again, but that can be risky in most of the situations that it can be used in comparison to the other methods (except for it being used like Fox's Bair to cover the illusion and stuff like that).
All in all, what your friend should be doing with Falcon is to control all of his movement options to create pressure on his opponents and use the previously mentioned techniques and edgeguards. Once he's comfortable on that end, then he can look forward to stuff like optimizing his punish game going on combos from 0-death or at least 70-80% or exploring more of the newer options that even the top players are trying to explore.
