I was an out of field applicant (linguistics and computer science), and as far as experience, I emailed a few local hospitals and rehabilitation facilities to see if I could shadow/observe. Some already have graduate students that they are busy with during the school year, so I offered to shadow over my winter break, which they approved.
This is (as far as I can remember), the e-mail that I sent:
"Good morning, ___:
I am a senior at ___, and beginning to apply to Speech Pathology graduate programs. The majority of these programs suggest that you fulfill some or all of your observation hours (25 hours total) before you begin graduate classes.
I noticed that ___ allows student observation, and I was wondering if you allow undergraduate students to participate in these observations and if I could complete them when I come to Houston in January."
I also worked as as a research assistant in multiple labs on campus (that weren't necessarily related to my major). One worked with children, and one mapped brain images. I was able to say how these related to my future career in my statement of purpose. If your university offers research opportunities, I'd look into that!