I don't have the disk how can I install for free?

Visit printer manufacturer's website, download driver/software for your printer and operating system, install.

If its not on the maanufacturer's website, goggle the name and model of your printer and type "drivers" after the name and download it from one of the sites.

You can download from internet respectively your printer manufacturer's website. You will get the free of cost. You have type your name of printer and serial no. for printer driver. Or also can find out from driver download.com