The nature of Mars (Kuja) is fire. He is deemed to be malefic. He is the lord of two houses in the Zodiac, namely Mesham (Aries) and Vruschikam (Scorpio); Makaram (Capricorn) is house of exaltation (Utach) and Karkatakam (Cancer) is the house of debilitation for Mars. Budha (Mercury) is enemy to Kuja (Mars). Ravi (Sun), Chandra (Moon), Guru (Jupiter) are friends to Mars (Kuja; Mangala); Sani (Saturn) and Sukra (Venus) are neutrals (neither friend nor enemy) to Mars. But Mars is enemy to Saturn. Mars is neutral to Raahu and Kethu. Venus and Mars are mutually neutrals. Sun and Mars are mutually friends. Mars is neutral to Moon. Mars and Jupiter are mutual friends. Mars has retrograde (vakra-gathi) motion and also stand-still (sthambhana) state. Due to this stand-still characteristic Mars (Kuja) can stay in a house (rasi) for more period than is usually destined).
If Mars (Kuja) is ill-disposed in any horoscope, some remedies are prescribed in Hindu astrology. (1) Recite (Japam) of Sri Subrahmanya manthra 108 times thrice a day. Perform milk abhisheka and ashtothara puja to Lord Sri Subrahmaneswara on one Tuesday every month. Do japam (recitation) of Kuja sthothra manthra 7,000 times every month during Kuja periods.
2) You can chant the following mantra for Kuja dosha nivaaranam, 108 times daily, during the malefic periods of Mars: "Om Namo Mangale, Mangala-adhaare, Maangalye, mangala-pradhe, Mangala-artham, mangaleshi, sou-maangalyam che dehi me; aayu, arogya, aiswaryam dehime dhiyam !"
(3) Wear a gold ring with a coral (pagadam) to the left hand ring finger (anamika).