Tuition is a way to enhance the learning among pupil.
Many pupil opt for tuition to improve their score in exams or to improve their knowledge in some subjects which they feel tough.
So we see many students coming for tuition specifically for science and mathematics subjects. Also for getting ready for competitive exams by getting command over subjects which they consider tough to tackle.
So a tutor has a good responsibility to deliver his service in right way.
How to be a good tutor:
Any person with sound knowledge and good level of education can take up tuition as a career.
1. Opt only those subject you love and are interested: If you decide to be a tutor, select to assist in only those subjects you love and are also very interested. Some of us could be interested and well versed in science but not in mathematics. You may find mathematics to be too difficult for you since childhood. In such a case, it is better to opt to teach only biology subjects. This is because, if by chance a pupil asks you to solve a physics or chemistry subject problems . Then you may find it difficult and also embraced if you could not answer it.
2. Understand the student: When a students comes for tuition he has some expectations in his mind regarding the tuition. 
The expectation can be like he is unable to comprehend mathematics or science derivations etc and hence wants help with them. So if a tutor understands these issues of the student then he can help him overcome those problems. If a tutor fails it means he could not satisfy his students and one of the reasons for this is he could not understand their needs.
3. Be well prepared for tuition before hand: A tutor should be well prepared before he goes for tuition. If he is not prepared with some subject he is going to discuss, he will loose the confidence of his students. The students may be tempted to look for other tutors. So tutor should be prepared about the subjects he wish to take up and also any new developments.
So be ready with books you wish to refer to during tuition. If the concerned books are not available at the moment, it will be an embarrassment to the tutor.
Also practice any diagrams in case you are not good at drawing on boards.
4. Give time to all: If you are tutoring for a small group of students, then you need to give enough time for each and every student.
In general those students who are less active or lagging behind in studies expect more time of you. If you do not give them time, they may dislike the tuition. On the other hand if you spend more time for those who are lagging behind then, you must make others understand that the particular students needs more time of you. For this you can first give time for active students and once you leave them for self study, you can focus on back lagging students.
5. Focus on subjects equally: when there are more than one subjects to teach in tuition. Give time for each subject. Focusing on one more than others may weaken students in that neglected subject. But also consider the students opinion in this time allotment for subjects. Because some subjects are easy for all students while some are tough to all. So giving more time for tough subjects is valid idea but it should be the same issue for all students.
6. Cover only those topics covered at school: Tuition is meant to help students in subjects already covered at school. So it is better to restrict teaching to topics already covered at school. This will provide ample time for tuition for intended topics. Also advanced coverage of topics before being taught in school will let students compare your teaching with that of their teacher. This may induce unwanted comparisons in teaching abilities.