Keep it in right proportion
Most people with fine hair find it easier to care for their hair when its shorter, but this is not THE Golden rule. Normally its better not to let it grow above your shoulder and trim them regularly to avoid split ends (that goes for any hair, but for fine hair its a must).
Level hair cuts make it appear much fuller in compare to layered cut. But in my opinion, let your hair grow as long as it looks healthy and manageable. In certain length it will start to go flat, so keep it in proportion to your volume.
Your need for special fine products increases as you grow them longer. Look for products that contain liquid keratin and silk protein as these substances penetrate and also coat the surface of hair and provide a much stronger and firmer structure. (In another word – it become thicker)
Some brands to look for:
Kenue Absolute Volume – With keratin and Wheat Protein
L’Oreal Serie Expert Volume Expand – With Calcium binder – Good for root volume
Bumble Bumble Thickening Shampoo and Conditioner – Tame flyaways and add volume
Hope these helps.N.F
