The phrase "burn midnight oil" means to work late into the night. However, there are many antonyms for this phrase that represent different ways of spending your time.
One antonym is "to kick back," which means to relax and do nothing. Another antonym is "to sleep soundly," which means to get a good night's rest. You could also "enjoy a night out," "spend time with loved ones," or "indulge in a hobby" instead of burning the midnight oil.
These antonyms offer different ways to unwind and enjoy your free time, without sacrificing your sleep and health. While working hard is important, it's also crucial to balance it out with rest and relaxation.