If I had to do it, I would try just starting a small talk conversation just to break that initial barrier e.g. ask her if she's still using blah blah equipment, or at the bubbler where you have water. Then over time you can progressively increase the conversation. If I had to direct approach I would go up to her, just introduce yourself, if you really struggle, you can disclose you have a stutter in a funny way, like not super serious. Shows you don't take yourself too seriously and then go from there.