I am a Google trainer, and I failed the re-certification exam after four years of teaching. Now I am done with this embarrassing confession. I asked my colleagues, also trainers. Here I am collecting their advice, with my comments.
- The exam got harder. Be humble and prepare for the exam.
- Study Google documentation, in particular, the description of the companies on which the questions are based.
- Cloud Guru course. It is two years old and has a 2-hours practice test at the end. Add your own knowledge and experience that you can get from QwikLabs.
- Question dump - you can find them on the web. They may be outdated and (very importantly) give you the wrong answers. At least the Apigee test dump was that way.
- Good luck!
- I passed, so it must have worked.