Rake
The rake is the tool you use to remove your marks from the bunker.
The rake, which on many courses is also called the rake, lies at the edge of every bunker. Its job is simple: after your bunker shot you smooth the sand, removing footprints and the spot where the ball landed. That way the next player finds the bunker in the state you would like to find it in yourself. This is part of firm etiquette and is taken strictly on well-kept courses. Since the 2019 rule changes you may also set the rake down inside the bunker without it being counted against you.
In practice the routine looks like this: you enter the bunker at its lowest point, play your ball, pick up the rake and drag it behind you with calm, straight strokes as you walk backwards out of the bunker. An example: your ball is lying near the bunker edge and your stance digs in deeply. After the shot you work on your stance marks first, then the impact area, then your footprints all the way to the exit. Finally you put the rake back where the facility wants it — some clubs want it in the bunker, others beside it; that is often on a sign or on the scorecard.
The typical mistake is hurriedly smoothing only the impact spot. The deep footprints on entering and leaving annoy the next player at least as much — a ball in a footprint is one of the most thankless lies. Take the half minute and rake the entire path. On courses without rakes, for example under winter rules or during maintenance periods, a local rule may allow preferred lies in the bunker — that is then posted on the noticeboard or in the frequently asked questions of the facility.
FAQ
Where do I put the rake back after a bunker shot?
The club decides, and it is not the same everywhere. Some courses want the rake in the bunker, others beside it — follow the sign at the bunker or the note on the scorecard. Since the 2019 rule changes, placing the rake inside the bunker is fully within the rules.
Do I really have to rake the whole bunker or just the impact spot?
You should smooth your entire path: the impact spot, your stance marks and all footprints from entry to exit. A ball in a deep footprint is one of the most thankless lies there is for the next player. Take the half minute — it is part of firm etiquette.
What do I do if there is no rake at the bunker?
Then the rule is: smooth it as well as you can with your club or foot and improve conditions for the player after you. During maintenance periods or under winter rules, the local rule sometimes allows preferred lies in the bunker. That is then posted on the club's noticeboard.