Kirby's Counter Picks

Don't spam specials like Down-B/Up-B. Even though Kirby is a very forgiving beginner friendly character, overly relying on these specials promotes bad habits. Don't spam his specials.

Abuse Down Tilt. Learn to abuse crouch. Also abuse up tilt.

Weak hits of f-air combo into f-smash. Use f-air close to ground, land before strong hit, and then f-smash. There is also a Kirby tutorial I recommend checking out by Juggleboy on YT

Don't worry about falling; Instead play aggressive to wall characters with bad recovery.

Don't get desperate! If you don't have a neutral-B ability for a while, don't sweat it. If your opponent sees you trying to get their ability, they'll punish you hard.