try to look kind (i think everyone does when they are in the same room with the one they love)
Try to look for infos like if she's single, has a crush on someone, by doing a truth or dare for example if you dare doing it. Or just by chatting with her about topics you want to get infos from her (sometimes it works, sometimes it wont)
Try to open your heart and mind when she's around and pay attention to what she says, you could find if she loves you back by the way she talks to you or interact with ya.
Try to do things that she loves/prob loves even tho it can costs you hours of learning something (example : i help my crush at writing a book shes doing and since my french and best seller book culture is real good, she loves the way I rewrite her book)
Try to show that you care for her, in a way or another.
Dont go in a way that could impact your relation