Q: Its a canon s520 and i don't know how to install it because i do not have the disk for it.
A: http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=330&modelid=6611 That should take you to the download page for the drivers for the s520. Download the drivers for your OS and you should be good to go.