Patch the nail or screw holes by slipping a bit of roof flashing beneath the shingle. Include a bead of caulk or roof cement to the top and bottom edge of the flashing to help keep it in place. Shakes are in essence shingles designed from wood rather than asphalt. https://arthurvyumn.thekatyblog.com/32518013/5-simple-statements-about-roofing-service-explained