The green diagram is the most information-dense section of any yardage book page. A well-drawn, annotated green diagram tells a caddy — at a glance — everything they need to advise a player on their approach shot and putt: the shape of the putting surface, where the dangerous slopes are, which pin positions demand which approach angles, and how the ball will typically behave once it lands.

Drawing the green diagram

Your green diagram does not need to be a perfectly scaled architectural drawing. It needs to be accurate enough to be useful and simple enough to read quickly under pressure. Here is what to include:

• The outline. Draw the rough shape of the green — is it elongated front-to-back, wider than it is deep, kidney-shaped, or near-circular? The outline does not need to be precise to the inch, but it should correctly represent the general proportions. A player reading your diagram should immediately recognize which green you’re describing.
• Internal features. Mark any ridges, tiers, or significant slope breaks within the green. A two-tier green needs a clear line between the upper and lower levels. A green with a prominent ridge running left-to-right through the middle needs that ridge marked — it determines which pins are accessible from which approach angles.
• Slope arrows. Use small arrows to show the direction of slope across different sections of the green. An arrow pointing toward the front-left of the green means the surface drains that way — and putts from that direction will run away faster. Cluster your arrows in the zones where slope most dramatically affects putting.
• Pin position zones. Most courses rotate through a set number of standard pin positions — typically four to six positions per green used on a regular basis. Divide the green into these zones (A = front left, B = front right, C = center left, D = center right, E = back left, F = back right is a common system). Mark each zone on your diagram and note, for each zone, the best approach angle and the most dangerous miss.
• Front, center, and back yardages. Mark three yardage references directly on the green diagram: to the front edge, to the center, and to the back edge. These become the three numbers you deliver on every approach shot — “154 front, 162 center, 171 back.”

Reading and using pin sheets

Many courses — particularly private clubs — distribute a pin sheet (also called a hole location sheet) at the start of each day. The pin sheet shows exactly where the hole is cut on each green that day, usually expressed as a number of paces from the front and a number of paces from the right or left edge.

A typical pin sheet entry might read: “Hole 7 — 4 from front, 6 from right.” This means the hole is 4 paces (approximately 4 yards) from the front edge of the green and 6 paces from the right edge.

To use this information with your yardage book: locate the “4 from front, 6 from right” position on your green diagram. Is this a front-right pin? Is it in your zone B? What does your book say about the approach angle for zone B and the break tendency from common approach positions to this part of the green? You now have a complete picture before the player even hits their approach shot.

Updating your green notes over time

Green notes improve with every round. After each loop, spend two minutes reviewing your green diagrams and adding observations: “Player missed left on 9 and it kicked hard right — the left fringe slopes severely right.” “Front-right pin on 14 — every player played too much break today — note: holds its line better than it looks.” These post-round observations, accumulated over a season, make your book more accurate than anything available for purchase.