You should be the reason what you've already study then you should make timetable of roster according to your merits and etiquette equal amounts of time sharing couple of hours to physics, couple of hours for chemistry and couple of hours of biology and additional hours of physics and biology is possible because these to high scoring and also high yield...
give special importance of the chapters of carbonyl compounds and nomenclature in organic chemistry, any currency in inorganic chemistry and molarity concepts and atomic structure concepts in physical chemistry, the chapters of genetics animal physiology, biomolecules and microbiology as well as biotechnology in biology and the chapters of electromagnetism, modern physics, mechanics and thermodynamics in physics
solve as many MCQ questions as possible to have a good grasp over your question selection and time management skills

Hii

Although you have not specified the name of the exam you are asking about but since you have mentioned that 4-5 months are left i suppose you are asking about NEET exam that is supposed to take place on 5th May 2019.
Here are some tips for you-
Now that only 4-5 months are left, you must be focused and prefer smart study at this point of time.
First of all you need to analyse the important topics as per the weightage given to each topic. Then focus more on these topic but remember to study other topics too.
Do not leave chemistry and physics they are also very important. Make a schedule on a daily as well as weekly basis and analyse your performance weekly to achieve successDivide your day into slots of 3 hours and them study. Do not stress out and be relaxed. Give rest to brain and body to stay active. Do not prefer late night studies. 
Go for online mock tests and also practice sample papers and previous year papers and time them to know where you stand. 
Score might be low initially but it will gain pace with time so do not get demotivated and keep on practicing . Stay confident and focused. Get some good books which will have all the questions topic wise as well as sample papers and previous year papers. 
Remember hardwork done with dedication never fails.

Also you can check this link. It is an initiative by career3360. Here you can get online tests, sample papers, previous year papers, etc.  https://www.entrance360.com/medical/neet/#courses

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