Whenever you see him looking at you smile and if he smiles back then hes probably smiling back because he likes you. If he gives you a huge just laugh a little to show him you like it when he hugs you. Whenever you see him with another girl just act like your mad but DONT say your mad because you saw him with another girl just play it cool that way he can ask whats wrong and he can have all his attention on you and not the other girl :)