All over preparation for IES is easy we can say even compared with GATE. Let us start with the difference in preparation for GATE and IES. For GATE, around 5 technical important subjects with Maths and Quantitative Aptitude may be sufficient to crack 95 to 98 percentile. We may have to even work out Exercise problems also for those subjects and may have to study multiple books for the same topic. But for Engg Service Exam (ESE), we may need not practice Exercise problems or may need not study multiple books for the same topic. Instead we may have to study multiple books for the same subject but for not same topic.
We need only 50% of marks from the written test. All over to write 20 to 25% questions, we need not prepare anything. Those will be that much easy. Around 40 to 50% of questions will be average standard which need preparation. Remaining questions may be difficult, for that above average to extreme preparation may be needed. Again, for ES exam, 30 to 35% questions (At least models) will be repetitive from Old question papers. So, we need to analyze old question papers starting from General Studies to Descriptive papers from 2004. Now, is it difficult to get 50% of marks IF WE PLAN PROPERLY?
PRACTICE! PRACTICE!! PRACTICE!!! Mantra. All you have to do is practice that’s all for IES. You have to do same example problems thrice. You have to read same topic in the SAME book thrice. You are done. You can expect IES. Frankly IES don’t need any talent, but perseverance and consistency in preparation.
About Objective paper: For objective papers we recommend preparing all subjects. For Electricals communications may be difficult or for Telecommunications Material science/Power Electronics may be difficult. But prepare those subjects also at least to Basic level. If you are unable to understand B.Tech books, go for Diploma books. You will be able to follow those and then try for graduation standard books. But don’t leave any subject. Old question papers from 2004, you have to prepare, least mug up those in few areas. Also prepare old civil services preliminary exam questions for objective.
About Descriptive papers: For descriptive we need to practice a lot. See 3 to 4 subjects which are important/which is carrying more weightage. Prepare all example problems; solve all old question papers for these subjects. For other subject prepare at basic level.
Objective is more important than Descriptive papers (THERE ARE NO MERCY MARKS WITH UPSC): We may get 70% of allotted marks, if we get correct solution with procedure for Descriptive papers. As calculators are allowed, we can expect problems which need to be solved properly with calculator. But for Objective, we will get 100% of marks, that to as they don’t allow calculator, we can expect simple problems, which need not be too much cautious.
General Studies & General English: General studies preparation is not much difficult task to do. We need to prepare last 10 years question papers for conventional side (Polity, Geography, History etc.,). Get an idea. Take year book and prepare least those mentioned topics from that. For current affairs, take Civil Services Chronicle from January to April. Prepare NCERT 9th standard and 10 standard Geography books. For polity you can opt for Laksmi kanth. As more questions come from Modern History (Preparation of Ancient and Medieval is difficult also J) you can prepare only Modern History. For this Spectrum Series book is more than sufficient. For General English, last 10 years old question papers are more than enough.
All over we can expect 120 to 140 marks in each objective papers, 90 to 110 marks in each descriptive and in General English/General Studies objective paper even if we get around 60 marks it is enough.