Yes, It is possible to crack UPSC without any coaching, But all you need is a good strategy and proper concentration towards your work. Follow a proper study regime for clearing the exam. Don’t overdo study by reading too many books instead just follow a single or two books for every subjects. Make Notes on the basis of what you read in the topic/chapters, underline the important points. Jotted down every important topic/point for future revision. Revision should be done regularly for better results. Avoid social media completely instead read THE HINDU, ECONOMIC TIMES for every information around you as well as with the World also. Don’t compare yourself with others just focus on what you are doing & Do it completely. Be regular with your Approach towards the exam or any other updates regarding it. Be more practical towards the exam. Do smart work as well.Once you cleared the exam with flying colors no one will ask you about the coaching, So better do it yourself.