Gaining an hour seems like a dream come true, but messing with your circadian rhythm (internal clock) can actually cause sleepiness. Instead of setting the clocks back an hour, start that Monday, or at least a few days before. Each night, set the clocks back 10 minutes so you can gradually get used to the new time.
And try to use this time of year as a check-in with your sleep schedule. If you haven't been getting enough shut-eye for months, adopt a new sleep plan where you go to bed by 9 p.m., get up at 5 a.m., and work out, and you'll feel energised and on top of the (dark) world).