How to Shrink Polo Shirts

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Hi everyone,

I have a collection of Tommy Hilfiger Polos I'm looking to shrink. They are all Large, and I now wear Medium. They are way too large in the stomach area especially. I have always hang dried them after washing.

I want to shrink them so they fit a little better. I want them to be tighter in my arms and shoulders to show off my work at the gym and in the stomach so you can actually somewhat see my physique.

I don't want to
* Discolour them
* Ruin their collars
* Ruin the shirts in any way

Do any of you have advice on how to do this, bringing them down between 1 or 0.5 sizes? Thank you in advance, I know nothing about little household tricks like this.