CAT

Its less than a month time and you know what they say, its all about how you will end the game.
Brush up your basics: It is high time that you have clarity on the concepts. If you have brushed up your basics, you will be able to tackle any question, be it a straight or a tricky one. Now that you have less than 30 days, ensure that you prepare fully on the important topics. Regularly practice and revise the formula, vocabulary and grammar rules.
Take full length mocks: The aspirants must have been used to taking mock tests by now. Along with taking the mocks, you should develop the patience to sit in front of the computer screen for 3 hours without hampering the focus and concentration. Regular mock tests will prepare you for the 3 hour test.
Develop a strategy how to divide your time and which section yo will start with. Start with your strong area, it time to get to know about your strength and weak points.
Do not start new topic- You should not take any new topics during this time, it will kill your precious time and won't help you in exam.
Revise as much as you can. Good luck.

If you are targeting this year's CAT, then this time you need to take as many mock tests as you can. Sit for 3 hours and give tests like a match practice. Do revise the concepts and formulas for the quant section because questions mostly become easy if you have all the formulas on your fingertips. Verbal communication needs practice and if you had done ample amount of prior practice of this section then you will get through this section. DI and LR need a bit of patience and concentration. Try to solve the questions after reading all the given conditions and key points. Take one or two tests each day and revise as much as possible.
If you are eyeing for next year's CAT, then start preparation now and dedicate 1-2 hours daily for practising quant, verbal and DI/LR. You need to give equal time to each section. Practice as much as you can.