Eighteen affirmations for leaders and managers — for the part of the job nobody trains you for.

Most people become managers by being good at something else. Then the thing they were good at stops being the job, and the new job — deciding, protecting, having the difficult conversation — arrives with no instructions and an audience.
These eighteen affirmations are for that transition and the years after it. Half are about being a leader; half are about the team, because leadership that is only about you is the version that goes wrong.
Teams read their manager's mood before they read anything else. That is unfair and it is also the practical reality: a calm, predictable manager makes everyone else's work easier, mostly by removing a source of noise.
So use these before the meeting rather than after it. Two repetitions of "I am a calm, confident leader" in the thirty seconds before a difficult conversation does more than any amount of reviewing how it went.

1. “I am a leader.”

2. “I can be a leader in my own way.”

3. “I am a born leader.”

4. “I am an amazing leader.”

5. “I am a leader to others.”

6. “I am a wonderful leader.”

7. “I am valued by my supervisors for my ability to inspire, lead, and mentor others.”

8. “I am a leader at work and in life.”

9. “I take on leadership roles and excel at them.”

10. “I am a reliable, valuable leader.”

11. “I am a visionary leader in the workplace.”

12. “I am a leader at work.”

13. “I embrace leadership roles and inspire others through my actions.”

14. “I build connections with my coworkers so we can work as a strong, united team.”

15. “I foster collaboration and unity among my team.”

16. “I inspire and nurture my team.”

17. “I bring fresh insights to team discussions.”

18. “I trust my decision-making abilities and so does my work team.”
Very few people are, and the ones who describe themselves that way are not reliably the better managers. Most of the job is consistency, clarity and follow-through, all of which are learnable.
Expect them for the first year — you have moved from a role you were demonstrably good at to one where competence is slower to prove. Naming it to a peer manager helps more than trying to argue yourself out of it.
"I am a calm, confident leader." Steadiness is the thing the other person will actually respond to, and it is the thing most easily lost in the ninety seconds beforehand.
As private preparation, yes — they work the same way here as before any other performance. This is a thirty-second thing in a corridor, not something to run in a team meeting.