How to enable Admob mediation in Unity3d?

Question

Unity

Hello, I was told on Habré that you can earn more with AdMob if you use mediation. I'm new to Unity and to connecting ads, I may not know a lot. As I understand it, mediation is the connection of other advertising networks to AdMob, and the point is that AdMob chooses the most profitable one from those offered by advertising networks before showing ads. The problem is that I did not find any tutorials on Russian-language YouTube on how to connect mediation with other networks. I just realized that for this I have to insert some kind of SDK into the gradle of my game with the initialization of advertising networks (from the AdMob manual). In general, I didn’t really understand anything. Maybe someone had experience with connecting this to Unity, what needs to be done for this? Do I need to register separately in each of the ad networks? Thanks in advance.