WHEn You liKE soME onE ANd DOEsNT kNOw How to SHow IT....?

what should i do? i qet very very very nervous arounnd the males i like. i do not want that to happen. i want to be friendly & show them that i am a great female. they usually make the moves first but i wanna take a chance and do the same. or should i stay back in my shell and let them do it? help:)