4. He will introduce you to his friends and family
If he really loves you, he will invite you to hang out with his friends. If he goes to office parties or friendly occasions, he will openly introduce you to everyone, and chances are that all those people would have already heard a lot of good stuff about you. Similarly, he would not hesitate to show you to his parents. He would not be shy, he would not be awkward, he would be confident introducing you to everyone he knows, which only indicates that he is sure about you.