How to get my ex girlfriend back?

this happened to me a few days ago. my bf dumped me and dated his ex gf. i won him back becasue i acted like i was over him wen i wasnt. i would flirt with his friends and have fun without him, she will see you having fun without her and it will make her feel like she made the wrong choice. this is playing hard to get and it works everytime for me. he wouldnt even stop texting me asking me if i was over him and i would simply reply no and go back to having fun :) my ex also got me back by relating his feeling towards me to a song, he said the song " best i ever had by state of shock" reminded him of me <3