Self-promotion can happen in several forms.
- Referrals - this is the best
- Articles written about you, interviews, panels
- Articles written by you, published on LinkedIn, Medium, blog
- Books written by you
Look like the best person in the world for the type of work that you want to do for the company. Identify who is currently the best in the world, and define a strategy on how to be considered 2X as well-known. It might take some time, but with a little creativity, shouldn't be hard.