@ashwint,
It is always better to wear the gemstone relavant to your horoscope requirements rather than your zodiac. However if you dont have an accurate or nearly accurate birth details, then you can wear the gemstone based on your moon zodiac but not sun zodiac. Reason being the moon transit an zodiac within 2.5 days and sun transits the same in 30 days. So for more astrological accuracy moon zodiac would be more accurate.
GOD BLESS!!!
Srinivasa Temkar