When following a wheel & Soft pedalling
When following a wheel the instinctive reaction is to grab the brakes when you see the gap closing to mere inches. But that’s the wrong way. Braking should be the last resort in a paceline /bunch riding or anytime someone is close behind. It slows you too abruptly and might cause them to do what you’re trying to avoid — hit a rear wheel
This is the art of continuing to turn the crank but slowly enough so that you aren’t applying power. You’re coasting but it doesn’t look like it. This should reduce your speed just enough. As soon as you drift back to your comfortable distance, begin reapplying pedal pressure to maintain the gap.
Soft pedalling makes you much smoother than alternately coasting and pedalling. Suddenly stopping and starting is a sure way to annoy your riding partners too. When everyone in a paceline is always turning their cranks, it’s a beautiul thing.
Two other non-braking tips :
Sit up. As you soft pedal, this helps you catch more air to reduce speed.
Move slightly left or right. This slows you more quickly by putting you slightly out of the slipstream, and it makes sure wheels won’t touch. Do it smoothly and minimally for the safety of riders behind. The flow back in line as you switch from soft pedalling to normal pedalling.