You lose an hour, in the spring we move the clocks forward one hour.. so.. if you didn't do that even though your clock says 6am it would actually be 7am (you'd be late!) so you set your clock forward and you are actually getting up at what used to be 5am.
You "spring" ahead for daylight savings time and thus lose an hours sleep. The change actually occurs at 2:00 a.m. If it were up to me, I'd make the change at 2:00 p.m. on a Monday afternoon and get out of work an hour earlier! But....nobody asked me.
You could go to sleep an hour earlier. They do it on Sunday on the premise that most people don't have to work on Sunday. Of course many people do have to work on Sunday so they have to go to sleep earlier or lose an hour of sleep.