I have to disagree here. The purpose of mask is to prevent you from transmitting it to the others as easily: The mask works by making sure if your nose is running or if spit a little when you talk or sneeze by keeping those particles contained, within your mask. Instead of being airborne and landing on something someone touches or being in the air and breathed in. Let's say you sneeze. The spit droplets that have the virus in them are now inside your mask, keeping others safe. Should droplet burst upon hitting mask the virus is still contained within the mask. Should the virus escape it would slowed down, when traveling by way of the sneeze, as the fibers of the mask works like speed bumps. This would not allow it to travel as far as an uncovered sneeze. Infecting less people if any.
The inside of mask facing you can get warm and damp creating a breeding ground. But that is facing you, again keeping everyone safe form the germs you may have.
For fitting the mask. Try putting the top straps above your ears and lower ones lower down you neck. If you need to adjust adjust the straps to avoid touching your face.