Hi Ivan! I’m glad that you enjoyed the article. I am actually going to focus more on analytical methods in another article, but for onboarding, I can summarize like this:
After determining the primary actions you want your users to take, I suppose the best and fastest way to test would be A/B testing and looking for the conversion rate. You can keep many variables constant and change a single variable — which could be UX copy, positioning of a button, a difference in the onboarding flow like less or more steps… You can then present the initial version to half of your users and the new version to the other half. According to the actions and conversion metrics you determine, you can easily see which approach works better. In a more general perspective, this testing method also works with the product itself. So as mentioned in the article, test, and iterate!
I hope this helps. Be sure to follow the series for a much more detailed and in-depth look at both quantitative and qualitative methods!