How could I make my t-shirts better?

nice work! it's cool how u made it

That's great work. Maybe with some liquid effect instead of smoke might be better but that's my opinion.

maybe you can add more depths by looking how the fonts look like embossed

I personally feel the style of the fonts and the graphics don't gel well. Maybe if the dragon was embossed/3D it might work better. Also try giving the art some breathing space, add negative space to the edges by reducing the artwork size a little so that the focus is narrowed towards the design instead of being scrambled across the entire square.

Maybe consider a more unified feel overall. Now I feel that the graphic image and photographic smoke are not completely in balance. Otherwise I love the design.

looks dope in my opinion, try it on black tshirt mockup

The best way to make them better is to keep making new designs consistently

Nice man, try keep all the elements the same so the chrome would be better for me with a more 3d rendered dragon and likewise, maybe a flat font with a more jap feel would better the work! Nice though!

Sometimes you keep overthink and you mess up with the design this looks good to me

Just put all things together I feel you 2d with 3d it doesn't go well together