Get back with my ex or nah ?

Okay heres a quick version of the story. I dumped my ex for no reason at all, mainly coz my mates told me. Stupidest mistake ever, and i hell regret it. its been abut 6 months now and we hardly talk. I told a mate who was also my ex's mate that i would really like to get back with him. My ex replied saying he would if i would "put out more & start talking to him again heaps. this doesnt bother me, but its really hard to start convos with him, and he rarely approaches me becaause of what happened before. what can i say to start convos with him with out it being hell akward.