Bandana scarves are, upon face value, square pieces of cloth.  As a rule they are approximately 22 inches square (although do come in both smaller and bigger sizes) and made from 100% cotton.  They have many names like bandanna, headscarf, kerchief, hankerchief, hanky, napkin, hijab, neckerchief.  There are many ways to tie the aforesaid square of cloth, a few examples are below:

"washerwoman" style - folded into triangle, ends tied just above fringe / hairline

"bandanna" style - folded into triangle, ends tied at base of neck

"headscarf" style - folded into triangle, ends tied under the chin

"hairband" style - folded into triangle, then rolled points first into a long, slim shape.  Tie ends at base of neck.  It can also be rolled the other way for a neater look.

"sweatband" style - same as above but tie ends at back of the head

"zandana / doo rag" style - as "bandanna" style but instead of tying the ends, gather together and secure with a rubber band.

Belt / jeans accessory - as "hairband" style but pull through belt loops of jeans and tie to make a funky belt or just pull through 1 belt loop and knot or tie and leave ends hanging.

"wristband" - as above but tie around the wrist and leave ends to hang.

"cowboy/cowgirl neckerchief" - as above but tied around the neck, fastening at the side in a knot.

You can also dress up your dog with these versatile squares!

There are many reasons other than fashion for wearing a head covering.  Many of our customers have lost thier hair due to illness or are about to undergo chemo treatment.  Bikers often complain of hairloss through the friction of helmets etc.  Construction workers and chefs may also benefit from wearing a headscarf under thier regulation protective headgear to provide added protection, cleaner head environment (you can't pop a hardhat in the washer!) and sometimes to provide a better, more comfortable fit for loose headwear.  Many ladies need to cover thier heads for religious belief.
Protection from the sun is also a good reason to keep a few bandannas handy.  Delicate scalp can burn easily even in the UK sun.
Whatever the reason, we may have something that fits your circumstances!