What tools are required for maintaining Airsoft Guns ? ? ? ?

Hello All..

As I am a newbie to Airsoft,so I didn't know much about this..

So I want you all to help me out please..

I want to ask that what are the typical type of tools/equipment/oils that I need to maintain my Airsoft guns (like keep them clean and ready to use)?
How often should I clean and maintain my Airsoft guns? If I use them everyday, should I clean them everyday?
Or what if I only use mine once every two weeks?

Hope this makes sense!