Can't really moisturize coded canvas like leather. But, you can still use leather conditioner. It's my hope it at least helps it not get brittle. I use Apple Brand leather cleaner. And Bickman Bick 4 leather conditioner. It seems great on vancheta leather. Doesn't darken it. But a little goes a long way. I'm not sure you have to sand paper it after the koat dries. You're trying to seal the end. Not make it thin enough so that it could split in the future.
the edges are applied more than 10 times so that it is not too thin. then the edges are sanded to remove any unevenness and finally the edges are painted again. I clean the bag to remove dirt and then a care product is applied to protect the varnish from abrasion.
