"You will advance your watch one hour on Sunday 25 March (at 2:00 AM) to be on summer time, and set it back one hour on Sunday 28 October (at 3:00 AM) to return to winter time."

Now that wasn't so hard, was it? (Of course, the instructions are for France and Western Europe. North America starts "summer time" a week later.)

In French, which is somewhat vocabulary poor, "devoir" means both to owe and to have to. "Devrez" is the future = "you will". "You should", which is how I translated it at first would be "devriez", conditional. But I have a feeling there may be a nuance for giving instructions, and "you should" is still a better translation.

Hey.....wake up!