Give him a sincere compliment
Make eye contact and smile
Send a playful text
Tease him lightly
Touch his arm or hand
Whisper something sweet
Dress in a way that makes you feel confident
Use his name when you talk to him
Laugh at his jokes
Tell him you miss him
Surprise him with a flirty message
Hold his gaze a little longer
Sit close to him
Initiate a hug or kiss
Be a little mysterious
Ask him playful questions
Praise something specific about him
Show interest in what he likes
Leave him a cute note
Be affectionate in public and private