When Ты know are thinking of them non stop for what seems like forever after and every time your with him или her your mind goes wt ease but your сердце beating like a drum over and over and over again.And above all when Ты know you'll never forget about them, that's when Ты say "I Любовь you." ^^
Not two days after Ты have just met, that is for sure!! If Ты say it too soon Ты will scare the other person off. It is best to feel for signs of that word being used frequently in an affectionate term to the other. Females tend to Любовь deeper или be еще hopeful. I personally think it is best to wait until HE says it (if that is the case...and even then I might wait.) That is just me. 'But once I do say it, prepare to be told that often.