1. Concentration needs constant reading. Initially you may not concentrate but once you start understanding the subject and go deep in to the subject,automatically you will love the subject and able to concentrate more. For this you must read consistently. Try to understand the subject first and then proceed furhter. In case of doubts, you must clear them with friends or teachers. Studying is not part time job. You must read daily for six days in a week all the possibel time and taking one day off from studies.

2. Memory comes from repitition. No body can remember if a topic is read once or twice. It must be read several times at different periods so that a permnent print is formed in the brain.
Some topics like numbers and data there is no other way except to mugup.

3. Scoring marks is different issue. you can do it later by preparing in an examination oriented way. Take previous examination papers, observe the mode and type of of questions being asked. you can notice some important questions being repeated several times. you must biheart those answers totally.

4. Have sufficient sleep and good balanced diet.

5. Keep away from T.V. movies for the six days in the week.

Work hard. You will success. There is no alternative nor magic nor any short cut for the success in studies.