Use a cloth then may it be shirt, jeans or even a rag. try also paper, bed sheets, pillows, cardboard, towel try anything you can that is atleast looks usable and try for yourself.
buy another mousepad -_- leather sheets are good. if you want some creativity you can make something layered with a cheap screen protector for tablets. if you don't wanna waste money, roll your mouse on your own thigh. make sure it's waxed.
A plain textbook always work... Something that have a single colour or consistent pattern and texture.