Hard to say, so I have to rely on anecdotes and what I see as a progression of steps that impacts salary. I suggest asking, "How does the quality of your program/mentor/internship" affect your fit and competitiveness with a given institution/clinical setting. I think this is important to consider as the setting and geographic location has a robust impact on salary. Perhaps this is different for people strictly doing private practice. Below is the sequence that unfolded for me and was similar for people in my cohort and other friends in the field.
1. Land an APA internship. I think the internship application process and eventual match outcome fits students in their deserved slots regardless of mentor and school. I understand this is a generalization.
2. Apply to a fellowship in-line with your area of interest and/or an area of specialty and need. This is often spawned from and reinforced by your internship training. Your supervisors should be able to provide strong letters of reference.
3. I was confident in my training as an intern and secure in the specialty I chose for fellowship (Addiction Psychology). This really helped me craft a well-formed professional narrative that opened up a lot of options for me in the job market.
4. Have a good understanding of the salary ranges across different clinical positions and environments. I had a fuzzy idea of salary ranges and knew what I was willing to accept.
5. The interview. At this point you should feel like you are interviewing places, rather than feeling like a practicum student willing to take anything. I found that geographic flexibility was crucial in this process and opened up so many doors for my career.
6. During your interview - Take yourself seriously, but with an appreciative humility. You are applying as a professional, not a student. Even though I applied to a job as an unlicensed postdoc, I needed to see myself as a licensed psychologist. The interview committee held me to that professional standard and I needed to do the same.
In the end, I felt like the interview committee asked me one question about how my university facilitated what they read on my CV. Otherwise, they were intently focused on my clinical interests, training, and what I saw for myself and the institution. The interview was more about fit that judging what classes I took or who mentored/advised my dissertation.