The Kirby? or the Dedede?
"King Dedede - There is a match that alot of Marth's just hate. It can be difficult to space well since his grab range is so long. Also he has his Waddle dees for camping and his f-tilt outranges all of your moves. Well thier are some simple things to remember in this match-up that make it easier. All of Marth's ground moves outrange Dedede's grab and a SH will allow Marth to go over Dedede's f-tilt and his Waddle dees. A SH fair is a great way to apply pressure and be safe. Good Dedede's that know this will try to go for dash grabs once they block your fair. Knowing this you can just jump or attack them when you see them try. Dedede also has a CG on Marth, but Marth can up b out of it. If Dedede expects this he can wait and then attack Marth while he lags. So it becomes a guessing game just like with Falco. If Dedede starts waiting for it, just roll away or set-up your zoning game. When Dedede is recovering you can run out and hit him since he is a huge target. If you force him to you use his up b you can counter it if he goes for the stage. If he cancels it then you have enough time to hit him back out and repeat the process. If he goes for the ledge, you will have enough time to hit him when he cancels it to grab the ledge, which will reset the situation as well. You could also try to edgehug him the moment you think he will cancel it to grab the ledge. He would fall to his death this way. Please keep in mind that Dedede is one of the heaviest characters in the game, so he won't die easily. Just be patient. His best kill move is his u-tilt, but you shouldn't be too worried about it if you are spacing well. He can edge guard pretty well thanks to his recovery, so if he goes out to hit you try to time your fair to hit him since he has no aerials that outrange yours. If you can keep him in the air it will be easier for you since he can't fight you there. His smashes are pretty slow so just roll away on reaction. His d-smash is good, but doesn't kill as well and is more close range so space well and you won't have to worry too much. Just take your time and don't get anxious to get in kills, because if you make a mistake you will eat an u-tilt and die around 100. Play smart. Play safe."
As for Kirby, he's a small target. Once you get used to hitting him I'm sure you'll be able to handle him much easier. Just make sure I don't get you off the stage. Once I get you off the stage I'm unforgiving ^^
My Creations in Modnation Racers! Check zhem!
http://community.modnation.com/en-us/players/IvoYaridovich/creations
