Here's what I know...
(1) If he ask you for plans at the end of a date with you, he is into you.
(2) If he wants you to meet his friends, he is into you.
(3) If he seeks your approval about things he could clearly decide upon on his own, he is into you.
(4) If he remembers little things you tell him when he so many things on his mind, he is into you.
(5) If he tries to please you at the expense of what is pleasing to himself, he is into you.
(6) If he makes time for you when he is clearly over-extended, he is into you.