Hi aggvipul,
To start, if your job isn't on a 'fixed' schedule, then your studies probably won't be either. While having a consistent study routine can often be beneficial, you don't have to have an established study schedule as long as you're studying in an effective fashion. For example, most people do their most effective studying in the first 4-5 hours of the day (when they're alert, have the most energy and are 'open' to learning and absorbing new concepts). Given YOUR work schedule, when would those hours be exactly?
I'm not sure whether we've ever discussed your studies before or not - so beyond the details about your job, it would also help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) How long have you studied?
2) What study materials have you used so far?
3) How have you scored on EACH of your CATs (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your goal score?
5) When are you planning to take the GMAT?
6) When are you planning to apply to Business School?
7) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich