how to flirt ❓❓❓

There's this one guy that I've been talking to for a while that I really like, but my friends say that I'm not flirting with him. We always joke with each other and call each one another pal and bud, but my friends say we're friend zoning each other. I always felt like we were flirting, but my friends' opinions have changed my views. I just want him to like me, but how do I let him know I like him without telling him straightforward?