To help you cure this problem I am sharing a complete skin care How-to guide added with 15 home remedies that are affordable and easy to follow.

1. Baking Soda

Baking soda has the texture of natural scrub, and it has been utilized for treating dead skin cells for years.

1.    Start with one teaspoon of baking soda and stir it well in water to form a paste.
2.    Scrub this paste gently on your knees and elbows for the period of 5-7 minutes.
3.    Rinse your elbow and knees with fresh water and apply a good quality moisturizing cream for nourishing.
4.    You can follow this treatment daily, twice a week or alternate days until you get the desirable results.

2. Turmeric, Honey, And Milk

Turmeric and honey have natural antiseptic and anti-inflammatory properties while milk in this treatment acts as bleach. Combining these three natural ingredients can make an effective scrub for the treatment of black elbows and knees.
1.    Mix the turmeric powder, honey and milk to form a thick paste.
2.    Apply the paste on your knees and elbows and leave for 20 minutes.
3.    After 20 minutes, rub the paste on the area for more 2 minutes for effective results.
4.    Repeat this process daily until you find the possible signs of improvements in your skin.

3. Lemon and Sugar

Lemon juice is naturally acidic in nature having strong antibacterial and antifungal properties. The mixture of both sugar and lemon will deeply exfoliate and even your skin tone in  a miraculous way.
1.    Take even quantities of lemon juice and grounded sugar and make a fine paste.
2.    Gently rub this paste on affected area for 2-5 minutes and leave for further 5 minutes.
3.    Clean the area with soap and fresh water to remove contained paste.
4.    Continue this process regularly or twice a week for proper results.

4. Lemon And Honey

Lemon juice contains a good amount of citric acid which acts as a bleaching agent while honey contains natural skin-saving antioxidants. The combined mixture of both these miraculous ingredients will deeply exfoliate and nourish dead skin cells of your elbows and knees.
1.    Start with Squeezing the juice from a fresh lemon and mix it with a tablespoon of honey.
2.    Apply the mixture on your knees and elbows and leave it for 15-20 minutes.
3.    Gently rinse and wash remaining paste. Continue this treatment regularly for results.

5. Gram Flour And Curd

Gram flour has been utilized in ancient times for its numerous skin benefits. Gram flour has multiple vitamins that can cleanse the darker skin areas and even the skin tone. Curd in this process will provide necessary moisturization.

•    Take half a cup of gram flour and add enough curd until it forms a supple paste.
•    Apply the mixture on knees and elbows and rub gently for 2-3 minutes.
•    After rubbing, allow the mixture to dry for 15-20 minutes.
•    Wash the remaining mixture properly with fresh water.
•    Repeat regularly until you get an even colored skin.

6. Olive Therapy

Natural oil therapies are named among the traditional and old methods of skin treatments. For this treatment, you can take any natural oil like sesame oil, rosehip oil, tamanu oil, olive oil, almond oil, coconut oil, etc.

•    You will be required to massage your elbows and knees for 10-15 minutes to deeply nourish and exfoliate the dry and dead skin of your knees and elbows.

7. Loofah or Exfoliating Brush

Loofah and exfoliating brushes are intended to scrub and remove dead skin cells from certain areas of body especially for darker elbows and knees.

•    Loofah or exfoliating brush can be utilized anytime, but dermatologists prefer using them while taking the bath. The skin, while taking shower is damper, supple which can make it easier to remove the upper layer of dead skin.

8. Cocoa And Shea Butter

Cocoa and Shea Butter act as good moisturizers and help to make the skin soft. This helps to remove the darkness caused by dry and flaky skin.

They are natural containers of healthy fats having properties of natural moisturizers. Their smooth texture and moisturizing ability can revitalized and help regain the softness and smoothness of dry and flaky skin. A number of dermatologists and skin experts prefer the application of Cocoa or Shea butter for longer hours especially overnight night for deeply nourishing and moisturization of dark elbows and knees.

9. Aloe Vera Gel

Aloe Vera has been utilized for ages as a natural ointment for the skin. Aloe Vera has natural antiseptic and anti-inflammatory properties that can reverse the of discoloration of skin.

•    Take fresh Aloe Vera and squeeze the gel from its leaves.
•    Apply the gel directly to your knees and elbows and leave for 30-40 minutes.
•    Gently wash the area with fresh water to remove the contained gel.

10. Sunscreen And Lotions

Sun exposure is the mere reason behind the discoloration of our skin. Regular application of sunscreen may reduce the possible chances of uneven skin tone while wearing t-shirts on sunny days.

•    Apply sunscreen on body parts that are more exposed to sun.
•    Application of moisturizers after a shower can also be useful for a fairer skin tone.

11. Vinegar And Yogurt

The balance of lactic and acetic acid between vinegar and yogurt works as a balanced potion to lighten the complexion of your skin tone. This potent mixture will not only provide a fairer skin but will also provide a soothing therapy to treat the darker areas and spots on your skin.

•    Gently combine and stir the mixture of yogurt and vinegar to form a thick paste.
•    Apply the mixture directly on knees and elbows and leave for about 20-25 minutes.
•    Once the mixture is thoroughly dry; wash it off with water.

12. Bleaching Fruits

Fruits like lemon, tomato and grapes have citrus flavor juice that contains bleaching agents. Many cosmetic creams and serums contain the extracts of these fruits as they are proven effective to cure a number of skin problems.

•    Take fresh orange or tomato, slice in half and apply directly on the skin.
•    Alternatively, you can make their juice and regularly apply  to the skin

13. Regular Moisturizers

Regular moisturizers are best treatment for revitalization and rehydration of the skin. The regular application of moisturizers will prevent the dryness and darkness of the skin while preventing the re-occurrence of dry and flaky membrane on the skin.

•    Apply genuine and quality moisturizer on dark elbows and knees right after shower or bath to keep your skin healthy, soft and supple for the entire day.

14. Natural Oils

Natural oils especially mustard oil contains moisturizing agents that help the skin to regain the melanin production. A pigment responsible for discoloration and dark patches that can only be recuperated by natural oils.

•    Natural oils like mustard, olive, sesame seed, or coconut oil must be applied to provide necessary moisture on elbows and knees.

15. Pumice Stone

Pumice stone is yet another natural mineral that is helpful to remove the dead cells from darker areas of the skin.

•     Rub the pumice stone directly on your dark elbows and knees especially at the time of shower or while bathing.

I hope these DIY remedies can help you get rid of dark knees and elbows. Remember, home remedies are not going to treat this as fast some medicine, but they are safer, better and long lasting without any side effects. I would prefer home remedy any day over some cream or drugs. Stay tuned for more home remedies and beauty hacks at my blog :)