Suppose you set your cruise control at a desired speed and then you apply the brake. This, of course, shuts off the cruise control. But you do not need to reset it.

Once you are going about 25 mph (40 km/h) or more, you can move the cruise control switch briefly from on to resume/accelerate.

You will go right back up to the previously chosen speed and stay there.

If you hold the switch at resume/accelerate, the vehicle keeps going faster until you release the switch or apply the brakes. So unless you want to go faster, do not hold the switch at resume/accelerate.