You can get 5 stars on an project by making your energy full. Your energy becomes full in 2 hours. So you have to wait, but it's worth it. Changing time won't help. If you change the time on your game, some janitor will say "are ya tryin ta cheat? Your clock has gone all screwy. Reset your game to fix this problem". You wouldn't want to reset your game right? So don't do the clock screwing.
Don't start a project when you have no energy. It will just waste time. Start a project when you have full energy. I know it's long, but worth it tho. You can easily get 5 stars if you play every 2 hours. It will get you to finish a project early with 5 AWESOME stars which will get you tons of fans. Hope this helped.
When you are not working on a project, not working at Starbeans and not dating you can simply go around and click on objects and they will sometimes give you energy. Objects include Newspaper Stands, cars and trash cans. After a short period of time everything resets so you can keep going around clicking things until you get enough energy for a date or project.