I would say that first of all, see whether she is starting to like you or not( if she's being flirty or clingy, etc). If yes and you are sure, then confess her right away. No point in delaying if both sides feel the same. but if you aren't sure about her feelings, then take it slow because if you confess right away she might think that you are one of those creeps wanting to be with every woman they meet. Talk to her for at least 1-2 months(get to know her more as well), and keep giving her signs from time to time about how you feel for her. If she asks you herself then say it right away, otherwise look for the perfect moment to confess. As to how to approach her, tbh I think that the best is to say it simply and straight instead of getting too creative that it becomes cringe. hope you get with her x