Cleaning guide (dirt under at the screen)?

Is there a good cleaning guide? I have found this:

But that doesn’t describe how to clean the screen. Is there an easy way to do this? If so, how?

Cool btw to see the inside of the OP-1 (this one isn’t mine). As i can see it isn’t easy to clean te screen. Also your warrenty will be gone i guess (text at the right bottom).