>>7613058
just keep using it, it's normal to feel bad wasting good paper, that's why every watercolor book tells you to deal with it in the first 5 pages, everyone goes through it and everyone who teaches it has to deal with students being afraid of paper
also, that's not much paper and the tiny block is kinda useless anyway, I have one lying around unused simply because I see no reason to use it over my pricier bigger paper