Get sufficient sleep to get six pack abs:

Getting sufficient sleep is also important for your body building. Doctors suggest that people who get more sleep are likely to lose more fat than those who sleep less. Stress controls your overall health. It also determines your body shape. So, you need to practice how to control stress.
Tip #1 – Make sleeping 7-8 hours a night a priority
Your sleep cannot be an afterthought in getting six pack abs. It’s critically important, and getting enough sleep needs to be one of your major exercise goals. Consistently getting enough sleep is just as important as consistently working out, or consistently eating right.
This is one of the big differences between guys who have a six pack and guys who don’t. Guys who have six pack abs treat their sleep seriously, while guys who don’t have a six pack neglect it then get frustrated when they don’t get the results they want.
Tip #2 – Reduce caffeine intake, especially after 6 PM
If you’re having difficulty falling asleep when you go to bed now, it may be because of caffeine. Caffeine stimulates your central nervous system, and makes it more difficult for you to get deep and restful sleep. Caffeine can be found in more than just coffee.  Check the other beverages you drink and even the food you eat for caffeine. You’d be surprised what it’s hiding in.
Caffeine can really hurt you if you are consuming more than two cups of coffee or two energy drinks per day. At this point, you are consuming enough to seriously interfere with your sleep.
Also, avoid consuming caffeine after 6 PM. Drinking caffeine this close to your bedtime will prevent you from getting sleepy, and disrupt your bedtime rhythm.