>>33219584if they seem to be alone then walk up to them, state your intentions, or try to strike up a conversation about the environment itself (i.e, if at a tourist attraction, talk about the attraction. if at a concert, talk about the band. if at a bar, talk about the drinks, food, or the bar itself and what made you decide to try it out).
worst she can do is brush you off in which case move on to another girl.