There are two ways to do it.
First, you can go around in one shot and re-set every clock that you have. Second, you can re-set each clock as you come across it, turning the time back immediately when you encounter it.
The one way not to set your clocks back is to do nothing when you come across one of your clocks that is still set to the old time, figuring you’ll do it in a little bit. That creates drag, because you’ll have to think about that clock several times before you actually do something.
OK, so almost everybody probably has their clocks changed already. So what’s the point? The point is that there is a lesson here in how to handle everything. There are some exceptions for sure, but in general, if you don’t put things off that you can easily do right away, you make your life a lot simpler.