Start with a clear question
Read 8.4 as eight complete overs and four valid balls of the next over. Write the completed overs and remaining balls separately to avoid treating the notation as a decimal.
Put it into practice
Use an imaginary scorecard and explain the notation aloud. Label every practice example clearly so it cannot be confused with live data.
Your next step
Keep your learning notes brief and return to a coach or the relevant official rule reference when a detail remains unclear.