Apple Watch band cleaning

I’ve has my Apple Watch 10 months and I’ve wore it quite a lot. One thing I haven’t done is Looked after the rubber band strap. I have the pink rubber band strap and it’s so dirty that it’s basically not pink anymore from all the dirt, gross I know. But does anyone have any tips on how to clean so I can get most of the dirt off. As you can tell from the photo it’s soo bad help is needed.