As we are all aware by now... summer is over (well, they call it summer anyway) and winter is starting to hit

What are the things I need to do to keep the engine running sweetly, prevent starting issues etc etc to make sure I dont run into any trouble over the coming months? And just keep it in as good a condition as possible all round? It is used on a daily basis and am aware that a regular hose down from salt etc will be needed.
Unfortunatly the mini is kept in the drive, and not garaged. I dont have a cover for it yet, but where can I get a half decent one from for as little money as possible?
Thanks
Joe