I found a great product called Buff Headwear which I always use for my "underscarf". I think some people call them bonnets or bones but the Buff Headwear does not tie on at the back like some underscarves do; it's basically an elasticated tube which you can bring over your head around your neck and then wear it like a wide headband and it keeps your hair securely out of your face. They are also pretty useful for when you are doing a facial pamper and whilst cooking or baking because your hair is kept away from your face and reduces the risk of stray straggly strands falling into your halal cordon bleu. There are even winter ones now for extra warmth if you are going to be venturing into the harsh elements!
Not only can they be used as underscarves for under your hijab or headscarf, but they can also be worn as a beanie hat, used as a scrunchie, hair band, headband, neckerchief, wristband, balaclava, bandana, scrunchie, pirate cap or saharaine.
In cold conditions, the Original Buff will keep you warm, while in hot conditions, the fabric wicks moisture away and cools you down. The Original Buff is made from a lightweight breathable fabric which is also wind resistant and very comfortable to wear.
The Asfora Tunic Dress comes complete with a tubular underscarf