3 months is ample time to cover Current Affairs before the preliminary Examination. Let me elaborate on the two approaches which I have tried with respect to this situation. Both of them have worked for me and should work for you too if you follow it with 100% dedication.
1st approach
- Go to the insights on India website and then copy their entire Daily news snippets to Evernote and then create and index month by month. It doesn’t matter which website you copy it from, but you should rely on a single source and create your own copy. Below is the picture of the notes that I created.

- Now comes the important part. Depending on the number of days left for your prelims, you should divide the number of days you need to finish. Say you have 3 months left and you need to cover a total of 6 months, you need to finish 2 days worth of current affairs in a single day ( That is the day on which you are reading and the backlog that you need to cover). This is without taking into consideration revision. In my case I always left enough room for revision.
- Religiously read the notes.
2nd Approach
Download the monthly snippets from a website like visionias and finish it religiously. I have tried this method too and can vouch for it.
Personally I like the first method because I love evernote more and the fact that it is a text based note. I love the final look of the notes in my computer or iPad. In the end, whatever works for you, works for you. Don’t get hung up on the method. All that matters is you have read the material atleast once so that even if a question that you don’t know 100% comes, you can take an educated guess.