Odd, I thought I posted on here earlier but its gone. Depending on ATO they should have the course arranged into modules or at least a study sequence within one large module.
EASA allows the subjects to be grouped into modules so you study, say, 3 subjects then do the exams, study 4 more then do those exams etc.
Unfortunately not all States have absorbed that and some require you complete all the study in all the subjects before you take your first exam. I think Poland at least might do this.
If this is the case for you, and you cannot split the course into modules, then you have a larger problem because of the problem of retaining all the knowledge from all subjects at once, and as Martin says that is hard. My advice would be to complete all the study as best you can to get the exam entry qualification, then revise subject groups in your own 'modules' before taking the exams in three or four sittings.
An alternative option is to take your exams with a more compliant State, and many use the UK for this purpose because, as much as we moan about them, the UK CAA are proactive and competent compared to some Authorities. In order to do this your ATO would have to be prepared to sign you off for the exams module by module, which is common practice in most EASA States.