At the first stage is the Situational Judgement Test. This is to assess your character profile and compare it to the Cabinet Office's character profile that has been proven as a best fit for a successful Fast Streamer.
As this is more about your character it's hard to formally coach so we don't. If you book the E-tray coaching we do normally cover the mentality and approach as part of that if you wish.
There are plenty of websites and examples on the internet.