Best or most friendly way to sort post order frontend

I’ve got a WP site with a custom post type called products, it also has a category taxonomy attached.

Everything is working fine but the person who’s going to use the site would like an option to order or reorder the output display of posts..

He has 3 products with almost the same name/title only one product is type small, medium and large. It would be great if they could also easily show up front end in this order without changing the post date all the time.

I’ve tried the plugin Simple Custom Post Order but this plugin doesn’t seem to work anymore.

Thanks for the help already.