Knitted masks

Are you going to line it with some sort of other fabric?
Knitting on its own would not keep anything out would it?

There are videos with detailed instructions for knitted masks on YouTube. As Maw said you would have to line them with a non cover fabric or a folded tissue which you can change each time you wear it.

Would they be rather hot if summer is coming?

Even ordinary thin masks can be uncomfortably hot.

I wouldn’t have thought a woollen mask would be very practical.

Masks need to be carefully removed without touching the outer surface and washed at 60 degrees after each use. We have to assume they have been contaminated and as such can’t be worn again without washing.

Disposable masks are only intended for single use and a fresh one required each time.

Trying to reuse a mask without washing would be like going home and not bothering to wash hands.

I saw a disposable mask on someone yesterday which looked very grubby as if it had been worn multiple times.

It looked like a health hazard

I want to knit with cotton yarn and I have a beautiful yarn I can use to make some..

I'm good at following instructions- but not creative! I'll look at the video, but suspect I need a pattern.