How to add custom page title to only the home page

How do I add a custom page title to my homepage that isn’t carried across the rest of my pages?

Currently my site’s name comes up for the home page (ie “Nike”). The rest of my pages have that name show up after the page name in the page title like “Running Shoes | Nike”. How would I alter my homepage so that I could write something like “Just Do It | Nike”, but it won’t carry over to the rest of my pages and I end up with “Running Shoes | Just Do It | Nike”?

Thanks!