You can try different techniques to get more from it but all you can do is try to grow a big healthy plant. When they say 'per square meter' 500 grams or whatever, think of a plant in a cubic meter pot under a thousand watt light, or outside. It's kind of fun to guess but you have to give the plants what they want, more light, a bigger fan, bigger pots and maybe a different medium. A flood table, like ebb and flow with watering every 3 or 4 hours got me some of my best yields indoors. bend it and tie it to a stick and it should start to branch out.