I study chess hard, like 4 hours everyday, and I still suck. Story of my life, study hard, and suck at it anyways, no wonder I droped outta college. I'm seriously starting to get peeved off with my lack of learning/studying ability and it sentancing me to a life of poverty. *gives god the middle finger*
30 minutes to 2 hours each day but i normally focus on something until i understand it by heart (e.g., practice the lucena and philidor positions so that i know how to draw or win). otherwise it's just tactics exercises using sharpen your tactics by anatoly lein, chess tactics art or chess mentor.