Hi
For theory part of all group 1 subjects, i advise you to study institute modules and update some of those content with amendments from website of that particular chapter, because they are nicely explained in a simple manner. Regarding practical problems:
Accounts-Hanif & Mukherjee or PC Tulsian or Shukla Grewal (u choose one set by verifying in shop which language is easy to understand) all books r nice.
Law ethics and communication - Inst. module or Munish Bhandari
Costing- P C Tulsian
FM - PC Tulsian
Taxation - Singhania.
For all theory parts, I advbise you to study the theory content given only in Inst. module. In addition, one must refer d suggested answer of previous papers and RTP, MTPs etc contained in ICAI website for download. Having a correct study timetable and sticking to it will help you to score good marks and without tension in last months of exam. All the best.