How to shrink a Calvin Klein undershirt?

I recently purchased a Calvin Klein undershirt, and it is WAY too long for my body. (I am a women, I buy the shirts for comfort) Is there a way to SAFELY shrink the shirt without ruining the collar?|||if the undershirt is 100% cotton you will get it to shrink including the neck area , the other way would be to cut it shorter and sew a blind hem on it or serging it , if you can do this yourself it would be great if not bring it to a seamstress and get her to to do it. If you wash your lingerie in cold water they will last and keep their appearance for a long time .