I just cant make a conversation

ok where i live thres this area where i see hott gils my age all the time so many of them. I do the usual i give them a smile some times they look scared and some times they give me a smirk back lol . But i dont have any clue on how to go up to a random girl im the music store there or any where else and just start a conversation does any one here have any good ways to spark a coneresation out of nuthingness? any help appreciated

if you are usually nervous just think of the worst case scenario. she is not intrested in you. it wont kill you its not even that bad. you can just find someone else

i hope this helps