IPMAT

Time institute near by for doubt clearing and help or you can study with internet by solving Mock papers of previous year Ipm paper. You'll need to be constantly updated with your Gk, keep your vocab up to date and be comfortable with qualitative or quantitative ability.
3 months dedication with proper and honest mock paper solving a bit of help from your teachers in math or other quantitative skill questions regular Gk knowledge and dedication will be enough for Iims IPM exam
On internet there is more than enough ipm material which can be very helpful. BUT if your basics are weak then you can also join a coaching class nearby maybe Time institute. Personally, I feel coaching is not required for IPMAT as the kind of questions which are asked cannot be prepared per se. One can only work on their speed and ability to tackle questions differently. I would suggest an aspirant to take a correspondencecourse or a test series. For that any reputed coaching centre should be ideal. Still, I would recommend against taking coaching classes for IPM as they are really not worth it.

Strategy to prepare for IPMAT:
1. All the questions in IPMAT are concept driven. Hence a thorough understanding of the topics is very much required to tackle the questions in IPMAT. Prepare the concepts thoroughly and revise them regularly.
2. IPMAT checks your knowledge and is all about managing time in the examination. Hence it is necessary to give mocks in actual test-taking conditions which will help you to score well.
3. Once you give the mocks, analyze the mocks thoroughly. This will help you to assess your strengths & weakness and you can devote extra time and effort to improve the weak areas.
4. Practice does make a man perfect, it is all about practising and how quickly and accurately you solve the questions. Hence, it is necessary to practice and study regularly.
5. 60% of the paper is from the quantitative aptitude section. The questions will be from all the topics of maths, hence it is necessary to concentrate on this section and score well.