Climb up onto a ladder to access the corrugated panels, using caution as you walk on them due to the wavy surface. Walk to one end of the roof and locate the seam where the first row of panels overlap the second row.
Insert a tube of butyl caulking into a caulk gun and snip the end off using sharp scissors. Apply a 1/4-inch wide bead of caulk over the seam where the two panels overlap. Work your way across the entire roof to apply caulk to all remaining seams to seal them.
Wait 24 to 48 hours to allow the caulk to cure completely before proceeding.
Rinse off the roofing material using a garden hose and remove any stubborn dirt stains or loose paint chips using a wire brush. Allow the corrugated roofing to dry before proceeding.
Pour a roof sealant into a paint tray and insert a paint brush into the sealant until it is saturated. Paint the sealant onto the entire top surface of the corrugated panels from the top to the bottom, working your way toward the ladder as you apply it.