How do you know if you have found your twin flame?

According to the Twin Flame Soul Mates website, there is usually an "unusual synchronicity" surrounding the first contact between Twin Flames. Once they've met, the Twin Flames feel very comfortable and open around each other, as though they're already very close.

Twin Flames have a love that is completely unconditional. Some people dream about their Twin Flame prior to meeting them. In the dreams, they have a strong, strange feeling their Twin Flame really exists in the real world outside of the dream. Upon meeting their Twin Flame, they may discover that their Twin Flame was also dreaming about them before they met.