Help!!!!

Alright, this is going to probably be the WORST, most stupid question I have ever asked (apart from the time I asked my friend where Leeds Fest would be.....FAIL) but here goes. Does anyone know how to make a bandana? Is it just like a square of material with a hem or what? I need to wear one because I can't wear a mask so I would really love some help! Also, thank you to all the killjoys who suggested a bandana, you guys rock!!!!!! Keep It Ugly!!