if u know he hasnt had his first kiss yet, when texting/talking to him be like "hey have you had your first kiss?" then he will say, "no u" then u should say "yea, but want me to teach you?" this works! kids do this all the time, it works!
if he has, just lick your lips, stare at his lips, hug him, hold his hand, snuggle, just be close and flirt and drop some hints(; GOOD LUCK(;