This matchup is so fun.
You can combo Falcon, he can combo you. It's just back and forth awesome. Also Yoshi won't get gimp edgeguarded at low percents. It's just starting the combos that's troublesome for Yoshi, and easy for Falcon. That's why he's high tier.
Fair as usual is a good starter, but only feasible if you jump over a raptor boost or otherwise mindgame him.
Utilt is great, but it only is good when he's not in a position to nair you (i.e. you're behind him)
Usmash is like a super utilt, it has more power and priority. Can work at the right percents, and is safer than utilt if the Falcon is committed.
Dtilt will leave to tech chases which leads to:
Grabs! Grabs work! You just have to know when he will shield, because its so easy to just jump out and stomp you. But Yoshi barely grabs otherwise so its pretty easy knowing when he will shield.
Uair is mostly a mid combo move but it can work if you midair crouch cancel his stuff.
Try to get one of the above moves off. Ftilt, nair, fsmash and neutral b can all be used to punish falcon if he doesn't like getting in position where you can combo him.
Also edgeguarding is easy dsmash or edgehog basic basic stuff. But otherwise dsmash is difficult to land, because falcon is either dash dancing, jumping, or shielded.