I’ve never really thought about it. I’m not a fancy skater – my skates do have brakes, so my technique isn’t such that I have to plan for never using them.
If I have the width I’ll slalom down hills to bleed speed - even doing little loops up the hill at the turn of each switchback to bleed off speed. If there’s not enough room to slow down, I might bomb though if it’s safe to do so (because that’s why roller blading is so fun, anyway). I might skate on one foot and drag a wheel behind or make my toes point toward each other slightly, just out of parallel - the greater the angle, the more drag the out of alignment wheels produce. I often tend to drag a wheel or use the brake, then spin to stop, before resuming.
There are other techniques for stopping or slowing down, but those are my go to’s.