TL;DR
If you just started working as software tester in team that is Agile, you probably have asked yourself how to effectively contribute in Agile team as new software tester.
Software testing approach
BBST Foundations states that software testing approach is:
Testing software involves investigating a product under tight constraints.
As a software tester, your main goal is not to master some software testing tool, like Selenium or Postman, but you must strive to ultimate skill of every software tester. You must become a better investigator. If you are software tester by your choice, you probably like Sherlock Holmes novels or Dr. House TV show. If you are “forced” into software testing, check them, because those could be a really eye opener for young software tester.
But what about tight constraints? In Agile team you probably experienced one, sprint duration of two weeks (or if you are out of luck, one week). Another constraint could be your software testing skill. Do not despair, because constrains will follow you during your software testing path, you just need to gain skills how to handle them. Reading software testing book is a good start to cope with knowledge constraint.
You need to become Context Driven. Every software product is different. There are many variables, and Agile team is one of them. That means that you must not blindly follow software testing practices that are used by other testers. You must explore and investigate them, and then apply them to your Agile team context.
There are no best practices, just practices that are useful in the appropriate circumstances.
What is next?
If statement that there are no best practices sounds philosophically to you, I am living proof that this statement is true. I was infected with this statement in 2010, and since then my software testing skills are developed in context driven way. Keep following this blog post if you would like to start your journey as contest driven software tester.