You're on the green in regulation (congrats). Here's a quick guide to putting-green rules

What happens when you mark a ball and then it moves? What about before you mark it?

When two balls are equidistant to the hole, who putts first?

If a ball is resting against the flagstick but resting above the surface of the cup, is it holed?

Is your ball on the green if only a sliver of it is on the putting surface?

You might know some rules on the green, but did you have the right answer to all of these questions? If so, kudos. If not, it might be worth remembering these nine things about what you can and can’t do on the putting green.

1. You’re on the green if even the tiniest portion of your ball is touching it. And if it is, you’re allowed to mark it and clean it. This rule is important to remember when a golf course subtly changes from fringe to green, like when red dots mark the border of the putting green.

2. You can remove loose impediments or repair damage on your line of putt. Just be careful what you attempt to repair. Spike marks and pitch marks are fine to fix. Aeration holes can’t be fixed (it’s a two-shot penalty in stroke play or loss of hole in match play if you do).

3. If you accidentally cause your ball or ball-marker to move, there is no penalty. This includes when making a practice stroke near the ball. Just remember to put the ball back on its original spot.

4. If natural forces such as wind, water or gravity move your ball, what you do next depends on two things. If you marked your ball, replace it on its original spot. If you didn’t mark your ball, play from the new position.

5. You can rub a green to remove loose impediments, but you can’t do it to test the surface. You can also rub the green on a hole you just completed or a practice green to test the surface, but that’s it. Do it anywhere else, and it’s a two-shot penalty or loss of hole in match play.

6. If your ball is resting against the flagstick, examine it closely. If any part of it is below the surface of the green, the ball is considered holed. If none of it is, then you still need to hole out. And if you remove the flagstick and the ball moves, even dropping into the cup, you have to replace the ball on the lip of the hole before holing out.

7. In match play, if two balls are equidistant from the hole, you can agree to play in any order or resolve the issue with some random method. In stroke play, there is no penalty for playing out of order, so it doesn’t matter who putts first.

8. When required to take relief on a green for any reason, you always place the ball. Don’t drop it from knee height.

9. If any part of your ball is on the wrong green—meaning another green than the one you are playing toward—do not hit a shot from that putting surface. It’s a two-shot penalty or loss of hole if you do. You have to take relief off the green, including where you stand, and it can’t be closer to the hole. It’s a one-club-length, slice-of-pie-shaped area where you drop.