Remove the Bar and Chain, hose them down separately with warm water and mild detergent, blow dry with compressed air, pay close attention to getting the bar groove and oil passages clean, grease sprocket tip and spray chain and bar with fluid film to prevent rust. As to the powerhead, blow it clean with compressed air and use a stiff paintbrush for stubborn areas, pay special attention to the clutch and cooling fins. Now you are ready to remove the air cleaner cover and air cleaner, plug the carb with a rolled up rubber glove to prevent chips etc from entering the cylinder, use compressed air to clean around the carb and air cleaner, remove the glove and reassemble. Replace spark plug with recommended one from owners manual. Drain fuel and fish out tank gas filter, replace with new one. Add 1/2 tank of sea foam(no fuel yet) start and run till it smokes like crazy, shut down for at least 12hrs. Drain remaining sea foam, reinstall Bar and Chain, add fresh fuel and bar oil, run till remaining smoke clears and verify bar oiling by running at WOT in front of a log and look for a stream of cast off oil. Now is a good time to sharpen chain, if you are not comfortable doing it on your own, send it out during the sea foam delay.