Brew about 1–2 cups (240–470 ml) of organic coffee. The coffee should be organic, because non-organic coffees usually have added chemicals and preservatives. Be sure to use a dark roast coffee or espresso. This will help make sure your hair will darken with the coffee. Make this brew strong, by adding a little bit more coffee than 1–2 cups (240–470 ml) calls for.  You can brew the coffee however you want (a drip coffee maker, on the stove), but brewing your coffee in a single serve instant coffee maker might not brew the coffee as strongly as it should be to adequately dye your hair. Let the coffee cool and use it when it is completely cooled, or lukewarm. You can use any kind of conditioner to mix with the coffee. However, thicker conditioners might make application easier. Mix 1 cup (240 ml) of the brewed coffee, with 2 tablespoons (30 ml) of conditioner, and 2 tablespoons (30 ml) of the organic coffee grounds. Use a spoon to mix all of these ingredients together. If you have longer hair, you can increase the quantity of coffee and conditioner used. The exact measurements are not a rule, but more so a guide. Apply this mixture to your hair using your hands, and consider using a wide-toothed comb to spread the mixture evenly through your hair. Once you have added all of the mixture to your hair, consider pinning your hair up in a bun to keep your hair out of your face as you let the mixture soak in. Leave this mixture on your hair for at least an hour. After an hour, the conditioner may start to dry and harden.  Apply this coffee mixture to your hair in a bathroom with a mirror so you can contain any mess and see what you’re doing. Drape an old towel (one you don’t mind getting messy) over your shoulders. This will prevent any of the coffee mixture from falling on your clothes and staining the fabric. Rinse the coffee and conditioner mixture out of your hair in the shower. Don’t add shampoo; simply let the water clean out the mixture from your hair. You may need to repeat this dyeing process a couple times...

TL;DR in Chinese:
煮咖啡。 将咖啡和护发素混合。 把混合好的染发剂抹在头发上。 洗头。