Preferably you want lights on at the very least 14 hours a day. And only going below that during the winter time.
I turn my lights on at about 8 AM and off at around 10 PM normally.
As far as diet goes this feeding guide should help. However, you do need to note that this varies between beardies and their current health. A beardie that just laid eggs or is gravid will need more calcium and food compared to a beardie that isn't gravid or laid eggs.
An example being two of my adult beardies. The 2 year old female began laying eggs, so I had to up her calcium and food intake. So rather than feeding her insects twice a week and only about 30-40 insects for that feeding day I had to feed her every single day and at least 60-80 bugs each feeding to keep her weight in check as she lost at least 80-100 grams each time she laid, I also had to give liquid calcium to make sure she had enough calcium in her so that the eggs wouldnt take from her bones. Her appetite also grew quite a lot during this time so she was eating almost anything you put in front of her which included salads, meanwhile beforehand she wasn't very big on salads and would mainly ignore them and opt for just bugs.
However, during this time my 2 year old male still ate twice a week for insects, needed no liquid calcium or extra feedings, his appetite didn't change too much other them him being a picky brat and wanting superworms as his staple.
The 10-20 bugs is also a minimum, I'd suggest doing how many they want in a 10-15 minute time frame each feeding instead.
All life stages eat 10-20 bugs a feeding.
1-4 months 3x a day.
4-12 months 2x a day.
12-20 months once a day.
20+ months twice a week at the least, every other day at the most.
Staple feeders - Crickets, locusts, grasshoppers, silkworms, black soldier fly larvae, dubia roaches, turkish roaches.
Treat feeders - Waxworms, hornworms, superworms, mealworms, butterworms.
Wax worms - once a week, 4-5 max.
Hornworms - every other day to every two days, 4-6 max.
Mealworms - every other day to every two days, 5-10 max. Only for beardies above 6 months.
Superworms - once or twice a week, 3-4 max. Only for beardies above 12 months.
Butterworms - once or twice a week, 3-4 max.
Daily greens- Turnip/collard/mustard greens, endive, and kale if added to a mixture of the other staple greens mentioned.
Fruit once or twice a week - Banana, strawberries, blueberries, blackberries, red raspberries.
For more food items -
http://www.thebeardeddragon.org/bearded-dragon-diet.php
http://www.beautifuldragons.com/Nutrition.html
Supplementation -
You want two supplements at the very least, a calcium and a multivitamin.
I recommend the Repti-cal brand but zoomed is also good.
The supplements should be lightly dusted on all bugs.
Generally, beardies below two years need calcium 5x a week and multivitamins 2x a week.
However, beardies above two years or at two years of age need calcium only 2-4x a week with multivitamins 1-2x a week.
This does depend on how your beardie is with diet, health, just laid eggs, is laying eggs, etc.