jigs advice
Ok first of all, you get SOLID edgeguards. As puff thats a huge thing. Your bairs/nairs offstage are spaced well. For 14, you're doing great. My little brother is also 14, so I'll give you some general advice since I don't want to bog you down.
From watching you play, you need to get used to calling your opponents moves, and responding to them. I know it's a little hard at first, but it makes a huge difference. Be less scared to just crouch, or wait in shield a second. You can't just throw out moves and hope your opponent will walk into them.
Ok. Next. You need to learn to wavedash. When you roll as much as you do, competitive players will capitilize on it and punish hard. What you WANT to do is wavedash. Trust me, it's a much smarter tactical move, less lag. Rolling is best used to get out of the way of an enemy attack, especially on with huge end lag. If you want to see effective wavedashing from a puff, just watch hungrybox. He uses wavedashing both defensively and offensively. A very common thing for a puff to do (something Hbox loves doing) is wavedashing backwards out of shield into a forward smash. You have to get out of the habit of Attack, roll, attack, roll, attack, roll. That's the first thing that will really elevate your playstyle
Also, like the guy above me said, you really need to learn how to l cancel if you want to play competitively. It may not matter when you play against your friends, but that extra 10 to 15 frames is all a fox needs to upsmash/ marth needs to f smash etc. Just listen to some chill music and practice it till you get it down. (fyi, the timing for l cancel on all moves is the same, 20 frames before hitting the ground, but you can see the effect better with certain moves than others. For jigs, try l canceling forward air. If you do it right, jigs should spaz out and do a "head banging" motion faster than usual.)
Ok now, you really should try to vary your approach a little. Even just changing spacing. Try landing behind their shield sometimes and jabbing/grabbing. I've noticed you really rock the auto cancel bair. This is not a horrible approach, but it's not the only one. Read about approach methods on the boards/ watch videos. A great puff to watch first is King, because he sort of invented the way alot of puffs play today.
And the last thing I have to say. Learn. To. Rest. Up throw to rest is your best friend against spacies. Learn it. Use it. Abuse it. There are so many combos into rest, just research it a bit. Sorry that this is a lot but I love giving new players advice
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