Sleep
Have you always wanted to:
1. Boost your immunity.
2. Increase your sex drive and performance.
3. Alleviate pain and inflammation.
4. Be happier.
5. Improve your memory.
6. Lose fat and gain muscle.
7. Improve your focus and concentration.
8. Live longer.
9. Acquire skills faster.
10. Recover quicker from phyical activity.
11. Reduce stress.
Maybe you've wanted all of them, or just a few. Either way, the simple method is sleep. And no, rationalizing your 4-6hr sleep schedule at night because that's all you need is not going to cut it. You can function off a lack of sleep, but you are not reaching your full potential. Furthermore, the effects of sleep deprivation will hit you at some point down the road. Trust me, I've had to change my habits because I thought I could pull off an uberman sleep cycle.
Let's talk sleep hygiene, and keep it simple.
establish a nightly routine which could include, listening to music, reading, or stretching.
keep your room dark and cool. No blue light from your laptop or phone before bed.
make sure your room is for sleeping, not set up to watch TV or do extra work.
The phrase, "sleep when you're dead" is a silly notion, which you can replace with the idea that you can work until your tired, but always respect your sleep time. If you don't sleep, you're a human zombie anyways. Sometimes we ignore the simplest advice, because it's so simple.
Sleep more. Naps are great.