I recommend finding a listserv for your subfield! E.g. I was interested in cognitive development, so I joined the Cogdevsoc listserv senior year and had lab manager job announcements emailed to me at least weekly starting in December. Not sure if there's something similar for clinical, social, etc., but it's worth asking a professor or adviser about.
I also second the "two year position if you can" advice...I took a job in a new state with only 1 year guaranteed (2 if grant funding comes through), and was overly optimistic about that second year happening until my PI made it clear that I should apply to grad school as a backup (I did, and we still don't know about the grant). I love the lab I'm in and would still probably take this job if I could go back, but the stress was intense. From September - December I constantly felt like I was failing either at research ideas, management, or the application process because it's ridiculous to jump right into all 3 at the same time. Thankfully my PI and labmates have been incredibly supportive and I did manage to refine my interests a bit in my 6 months here, so I might actually have a shot this cycle. But again, if you have a 2-year option that matches your interests well, definitely take that into consideration!