The fuel tank
Empty the fuel tank in a well ventilated area and then clean it. Remember to drain the carburettor to prevent the diaphragms sticking together.
Remove the chain and guide bar in order to clean them and spray them with a protective oil to help them last longer while not being used.
Store in a dry place
The chainsaw should be stored in a well ventilated area that is dry, dust free and out of direct sunlight. Storing a chainsaw outdoors is not advisable and it must be kept out of sunlight because it can cause UV embrittlement. Keep the chainsaw dust free by storing it in a chainsaw bag or case in order to keep it protected.
Always keep the chainsaw out of reach of any children with the best place to store it being in a lockable room with other tools or cupboard.
If a chainsaw is stored outside there is the possibility of it leaking oil. The issue here is that bar oil is stickier and harder to clean out of materials than regular oil.
A good idea is to have a few spares such as chains, spark plug, a starter cord and some mix oil and bar oil. If you keep these you will always be prepared for any issues you have with your chainsaw.