how is the the hair like in the army for females?

Hair needs to be kept off the shoulders so most females wear long hair tied up and put into a bun net or short no longer than a bob. You can’t dye it bright unnatural colours like pink. Basically it needs to be neat.

Does the hair have to be kept in a low bun or can it be a regular bun

can a female have a pixie cut ?

A pixie cut is perfectly accepted as it conforms with all hair regulations

Hair can be kept in a low bun at the nape of your neck, or a higher one, but you need to be able to get your beret on, so bear that in mind and don't make it too high!

Hair can now be worn as a plat or ponytail and doesn't need to be worn in a bun. As long as it's neat and tidy and off your face. Certain trades for health and safety reasons still will need hair to be worn in a bun (medical / chef etc)