For red hair, choose a color similar to your hair, but slightly ashier if you have pink tones in your skin. Brunettes should stay within 2 shades darker of your hair color. Black hair looks best with cool medium-brown eyebrow makeup. Dark brown hair should opt for espresso shades. This adds a bit more warmth than pure black while still maintaining a deep tone. For blonde hair, try for up to 2 shades darker than the natural tone of your hair. [1] X Research source
Apply your product as precisely as possible. You want to cover all the hairs, but you also want to stay within the outline of your brows to avoid unwanted tinting and staining. Wait 5-7 minutes for the dye to set in before moving on. [14] X Research source
These flowers are likely safe but check with your doctor if you are pregnant, breast feeding, have diabetes, low blood pressure, or are planning on having surgery. [19] X Research source
You can also add rosemary or lavender essential oils to olive oil to increase hair growth. [20] X Research source Be careful if you have sensitive skin because oil can cause breakouts. If you start breaking out, stop using the olive oil.
This will not darken the actual color of your brows, but it can help them appear thicker, which may make them look fuller and slightly darker.