Preparing current affairs should be an exercise of daily routine. There are multiple sources to prepare for current affairs such as newspapers, PIB, RSTV, monthly compilations, magazines, websites, etc. One must keep limited amount of sources (3-4) and stick to them as too many sources can result into unnecessary double reading as well as information overload.
Preparing current affairs is a note taking exercise in itself. Anything that one finds relevant to the syllabus must be noted. Notes can be made either in writing or in digital format. Most important is to organize notes. For those who prefer writing, I would recommend them to use loose A4 sheets to prepare notes and to compile them in files. This will help in assembling one topic at a single place. For those who prefer digital notes, Evernote or OneNote applications can be used. One must organize notes exactly as the syllabus is i.e. create files for every subject, for instance, keep separate files for Art and Culture; History; Geography; Social Issues; Indian Polity and Constitution; Governance, International Relations; Social Justice; Economics and Development; Science and Technology, Internal Security; Environment; Disaster Management and Ethics, Integrity and Aptitude. Within these files make notes of sub-topics.
I would also suggest aspirants to create an extra file in which one must compile Data and Facts; Quotes; Diagrams and Maps; Indices; Reports. This file will be used for last moment revision and will help fetch extra marks.
While preparing current affairs one must also try to bifurcate information as purely Pre specific and Main specific where-ever possible. An aspirant must also try to think as to what kind of question can be asked from that current affair and how to proceed with the answer. This will help in better understanding and preparation.