washing post op binder advice needed

sorry for all the posts

i just wanted to ask about washing my post op binder, i bought a children’s size small compression sports tshirt for while my binder is drying ( it already feels like it’s compressing more than my actual binder icl) but just wanted to know the best way to wash the actual compression binder. i’ve heard a cold hand wash in the sink would be okay but just wanted to double check!