How to be more than a friend?

im 18 and ive never had a boyfriend, i always speak to guys and i pretty much always like a guy in a more than friends way but just nothing happens between us. like i'll speak to a guy and he'll flirt etc with me, we'll meet up, act like we are in a realtionship and 'see' each other but just never be officially a couple. and then i'll realise hes just wanting to be friends and we'll keep on talking. its like guys like me, but they just dont see something to make them want to go out with me? im pretty confused at this, and i dont know what to do about it. im myself around guys, and im just really a normal girl. theres nothing particularly special about me but i dont think theres anything majorly wrong, except nerves when i first meet up with them, but they soon disappear. im speaking to a guy from my work atm, and he seems pretty interested in me. last night we were at a work leaving party and we were sitting in a group together, and we just spoke like normal friends (i didnt expect him to be all over me, but maybe a bit of flirting or arm around me) but when he texts me its more than friends kinda thing. im going round to his house tomorrow night, and i dont know whether to expect to just be friends or more... before i spoke to a guy for 4 months, never met up but text constantly and really liked him and tbh im not completely over him at all even though we havent spoken for nearly 4 months now (but i cant be bothered going into that). nothing ever happened with him. i dont know what i can do, is there something im possibly missing? how can i get a guy to like me more than friends?!