Against falco, I stand under a platform and then mix up my time to jump onto it. This makes falco have to decide to either jump onto the other platform to laser you or stay on the ground and laser. If you get on the platform and falco is still on the ground, try to move across the platforms to approach him. Ideally, though, you want falco on the platform lasering. Once he gets up there, then run under the platform he is on. He has a few options there like drop laser, drop dair, etc. You have to outplay him here to get a hit off.
Essentially, you have to use platforms to get into the space where falco cannot shoot lasers safely. Once you get inside of this space, which is like one or two wavedash lengths (not really sure), then you just have to outplay him. His best options in this scenario are to offensively aerial or retreat and laser. If you jump at him with an aerial it beats the laser option. If you both aerial in place, whoever spaces better wins.
Edit: Oh yeah, if the falco is playing aggressively, you need to learn how to shine/upsmash oos. You should still use the platforms, but if he's playing aggressively, you shouldn't be approaching. Just defensively move around to mess with his spacing and shine oos him.