I need some advice on how to approach a girl at the gym. I've seen her there a few times, and I've recently noticed she may an an interest in me (she uses machines next to me a lot, I catch her making glances at me, a little smile a few times).

My problem is that I've never really approached anyone I didn't know before. The last few girls I've dated, I met on tinder. I don't know what to say or how to hold a conversation when using small talk. So what is a good way to strike up a conversation with her without coming across as a weirdo?