If you do not have a cut out of material for the face covering please read the template posts and create a face covering material cut out.
For this part you will need an old t-shirt, some hemming web, an iron set at the required temperature for the hemming web, an off cut of material to use between the iron and the face covering so no glue gets on the iron.
There are a few debates on if to use elastic over the ears, these could be for a younger person who might find elastic annoying, what I use is about 2-3cm strips cut from an old t-shirt.

To turn these into strings or cords just stretch them using your hands, tug them hard and they will stretch into shape.

Lay the material front or patterned side down and fold the edge of the wings over by just over 2cm the width of the hemming web.

Open up the seam and place two strips of hemming web, you can just tear the hemming web, we use a double layer for strength.

Fold the seam over and press into place with the hemming web inside, use a scrap of material to protect the face of the iron, and follow the hemming web usage instructions.
Hemming web is a glue that fuses the two pieces of material togeter when heated to the correct temperature.

Please read part two for the rest of the steps to make ypur non medical face covering.