Get your recent 18-hole scores
Use scores from rounds played under acceptable conditions
Record the course rating and slope rating for each round
Calculate your adjusted gross score for each round
Subtract the course rating from your adjusted gross score
Multiply the result by 113
Divide by the slope rating
Repeat for each round
Keep the lowest handicap differentials from your most recent scores
Average the selected handicap differentials
Multiply the average by 0.96
Round the result to one decimal place
Use the result as your handicap index
Convert your handicap index to a course handicap using the course slope rating
Subtract the course handicap from your gross score to get net score