How do you clean your MacBooks ?

I regularly clean my macbook with a sanitizer. outside and inside (not the screen of course). But for the other parts I always let it go because it’s challenging.  Which honestly makes my mac look disgusting.

For screen: I taught about microfiber but I don’t really have a clean environment so it’s easy for small hard dirt to get into the microfiber and scratch my screen so I fear this solution. But even without that issue, I would need a cleaning product because microfiber alone wouldn’t be enough (it’s not only dust but also spots from dirty keyboard)

For inside: There is a lot of dirt that obviously got in because of the fans but also by going below the keyboard keys. I believe cleaning that (the dirt inside the laptop and below keys) and removing dust inside would require me to open the macbook which would vault warranty or repair wouldn’t it ?

Isn’t basically my sole and best option to go time to time to an apple agreed shop and ask for my macbook to be cleansed ? 

I am a little bit worried about that too because:

• price
• time to deposit it and time without macbook
• And because of the way people work in my country, it is likely to get damaged even if it’s minor like scratches, a blow in a corner, or anything…