To give you some positive feedback - I did like THIS shirt:
But just the front. The back was overkill (as are the backs on all of the shirts). I don't know if there's some magic number when it comes to text on shirts but I'm going to bet the cap is like 7 words or something. I would think that it shouldn't be so long that you couldn't read it as you walk by someone wearing the shirt. I mean, do you really expect people to stop someone wearing your shirts and stand there and read it?
I don't want to jump in the rag-on-OP fest, but god damn, your site's design... I mean, are you really taking your business seriously? Your website is your online equivalent of your actual physical location if you were an offline business. Are you going to sell T-shirts out of some rundown piece of shit brick building? 'Cause that's what your website is right now.
First things first - your header. Your header is basically your sign. Don't underestimate the benefits of having a good sign (or the detriments of having a shitty one).
Check out this mother fucking piece of art I created in 2 minutes with the text tool in photoshop:
The magic of a text outline, a dropshadow and some decent fonts - amazing, right? Feel free to use it - it's on me! Or you could hire a designer and get a really legit looking header with a logo and everything.
Now most importantly:
YOUR FUCKING CTA. WHAT THE FUCK, MAN?
You have this small ass "Buy Now" button that, when I click it, takes me to paypal. I don't even know what the fuck I'm buying. I hit back and realize there are drop down menus and
that's where I'm supposed to actually choose the shirt I want. What the fuck? Where are the individual product pages with the product image, description, size/color choices and a nice add to cart button? Why am I just getting sent straight to paypal to send some dude money? For all I know I'm gonna end up out $18 with no shirt. Close tab.