Is there a guide for creating Reflections for a specific query?

I am new to Dremio, and trying to accelerate some queries. Following the quick start guide for reflections and created some reflections, but I don’t see the query be quicker.

Is there a user guide for that explains how exactly the reflection works, and how to create reflections some specific queries ?

Thank you

We are working on an in-depth guide with best practices, stay tuned.

Meanwhile, did you try this tutorial: