It is going to be quite challenging as you are coming in contact with serious preparation for Civil Services Examination after a long gap.
You will have to indulge in a study-plan that involves topics from diverse disciplines; so, you need to plan it properly.
First, you should be clear about the exam-plan and related requirements at each stage of the examination.
You should prepare effectively so that you are able to crack it in the first attempt. So, if you are serious and ready to put in diligent efforts, you should commence preparation with some basic books.
The related article given below will help you in crafting a strategy of your own.
So, show courage and start your journey towards your destination - IAS