This is kinda off topic but here's what I've found seems to make Dresscode somewhat more impressive. Now I'm not sure what your presentation of the trick is but I do own the trick so I know there is a semi-obvious move you have to do when you want the shirt to change and a lot of people seem to pick up on it. Even though they might not know the exact mechanics work, they sort of fall back on the non-explanation of "I'm not sure what happened but I think it had something to do with that move he did." Which isn't ideal. To a spectator, a non-explanation like this is basically the same as knowing how the trick is done. That's one of the reasons most card tricks aren't always that memorable. Many people simply dismiss it as "sleight of hand" and are content with that explanation.
Anyway, my main solution to combat this is to not put a lot of focus on the shirt changing. So, either do the change unexpectedly in an offbeat or don't make the change the main effect.
For example, Nash Fung performed at our Grad Night and at the beginning, he took a selfie on someone's phone with everyone and it showed that he was wearing a shirt that was one color. He didn't draw attention to the color of his shirt but somewhere during the performance, he did the necessary move. Because he never made his audience focus on his shirt, no one picked up on it, including myself. At the end of the show he had us look at the pic and we realized his shirt changed color at some point during the performance and no one noticed.
Apollo Robbins uses a very similar presentation in his TED Talk:
https://www.ted.com/talks/apollo_robbins_the_art_of_misdirection
Another idea I've seen that works well is to not make the change the main focus of the effect. Julien Magic used Dresscode to make it seem like he instantly cleaned ice cream off his shirt:
You could also have the design on your shirt change slightly to reveal some kind of forced card or whatever. Basically do something that takes the main focus of the trick away from just the shirt change. It's almost like how you'd use a smoke device to enhance other effects rather than making it the main trick.
I recently had the idea to get two shirts that look almost identical except one has a breast pocket. So in the middle of another trick, you act like you need a place to put your card box or a sharpie and you magically make a pocket appear. I'm still messing around with it but it could work.
Anyway, sorry about that. I have a tendency to ramble. As I say at the end of basically every post I make, this is just my opinion and these ideas may or may not work for you.