As you want to get the details of preparation tips for the exam of Indian Engineering Service so here it is for you:

PRACTICE! PRACTICE!! PRACTICE!!! Mantra. Candidates must practise this mantra at least thrice

Candidates must refer basic English grammar books

Candidates must read newspapers and watch the news on TV regularly

Refer to as many latest GK books as possible

The preparation should be such that not a single topic is left out

Candidates must solve last year question papers as much as they can

Candidates must make a routine time table and just stick to that

IES reference books:
CIVIL ENGINEERING:
SUBJECT AUTHOR
Strength of Materials /Mechanics of Structure Gare & Timoshenko, E.Popove, L. Singer, B.C. Punamia
Theory of Structures/ Analysis of Structure S. Ramamurtham, L.S. Negi & Jangit, Gupta & Pandit, C.S. Reddy
Construction Planning &Management
(i) PERT -CPM B.C. Punamia
(ii)Engineering Economy & unsolved Problems on PERT-CPM U.K. Shrivastav
(iii) Equipment
PEURIFOY
Soil Mechanics & Foundation Engineering Gopal Ranjan & Rao,Venkat Ramaiha, S. K. Garg, B.C. Punamia
Fluid Mechanics and Fluid Machines Modi & Seth, R. K. Bansal, A.K.Jain K.Subramanyam, Jagdish Lal.
Environmental Engineering B.C. Punamia(Part I & II), S.K. Garg (Part-I & II), Peavy, Metcalf & Eddy
Highway Engineering Khanna & Justo, Kadiyali
Railway Engineering Saxena & Arora
Airport Engineering Saxena & Arora
Docks & Harbors’ Rangwala
Building Materials Rangwala, M.L. Gambhir
R.C.C. Design B.C. Punamia, A.K. Jain,
Steel Design S.K. Duggal, L.S. Negi,
Plastic Analysis Manicka Selvam

ELECTRICAL ENGINEERING:
SUBJECT AUTHOR
Electronic Devices & Circuits & Analog Electronics
(i) Integrated electronics : Analog and Digital Circuit and system
(ii) Microelectronic Circuits Jacob Millman & Christos C. Halkias Sedra & Smith
(iii) Electronic Devices and Circuits J.B. Gupta
(iv) OP Amp and linear Integrated Circuit Ramakant A.Gayakwad
(v) Solid State electronic devices
Streetman and Banerjee
(vi) Semiconductor devices S.M.Sze
Communication System
(i) Communication System Simon Haykins
(ii) An introduction to Analog and Digital Communication Simon Haykins
(iii) Communication System : Analog and Digital
(iv) Modern Digital and Analog Communication System Singh and Sapre
(v) Electronic Communication System
B.P. Lathi

Kennedyand Davis
Signal and System Oppenheim and Willsky
Optical Fiber Communication Senior
Satellite Communications Pratt and Bostian
Monochrome and colour R.R. Gulati
Control System
(i) Control System Engg. I.G. Nagrath & M.
Gopal
(ii) Automatic Control System B.C. Kuo
(iii) Linear Control System B.S. Manke
Electro Magnetic Theory
(i) Elements of Engineering Electromagnetics N. N. Rao
(ii) Elements of Electromagnetics
(iii) Engineering Electromagnetics Sadiku
(iv) Antenna and Wave Propagation W.H.Hayt
K.D. Prasad
Digital Electronics
(i) Digital Design M. Morris Mano
(ii) Digital Systems Tocci & Widmer
(iii) Modern Digital Electronics R. P. Jain
Computer Engineering
(i) Microprocessor Architecture, Programming & Application Ramesh S. Gaonkar
(ii) Computer Organization and Structure
Stalling
Microwave Engineering
(i) Microwave Devices and Circuits Liao
(ii) Microwave Engineering Sanjeev Gupta
(iii) Microwave Engineering Pozar
Network Theory
(i) Networks and Systems D. Roy Chaudhary
(ii) Engineering Circuit Analysis Hayt
Electrical Engineering Material science S.P. Seth
Measurement and Instrumentation
(i) Electrical & Electronic Measurement and Instrumentation A. K. Sahney
(ii) Electronic Instrumentation
H. S. Kalsi
Electrical Machine
(i) Electrical Machinery PS Bhimra
(ii) Electrical Machines Nagrath & Kothari
Power System
(i) Power System Engg. Nagrath & Kothari
(ii) Electric Power Systems CL Wadhwa
Power Electronics PS Bhimra

Electronics & Communication Engineering:
SUBJECT AUTHOR
Electronic Devices and Circuits & Analog Electronics--
(i) Integrated electronics : Analog and Digital Circuit and system
(ii) Microelectronic Circuits Jacob Millman Halkias
(iii) Electronic Devices and Circuits
(iv) OP Amp and linear Integrated Circuit Sedra & Smith
(v) Solid State electronic devices J.B. Gupta
Ramakant A. Gayakwad
(vi) Semiconductor devices Streetman and Banerjee
S.M.Sze
Communication System
(i) Communication System Simon Haykins
(ii) An introduction to Analog and Digital Communication Simon Haykins
(iii) Communication System : Analog and Digital
(iv) Modern Digital and Analog Communication System Singh and Sapre
(v) Electronic Communication System
B.P. Lathi

Kennedyand Davis
Signal and System Oppenheim and Willsky
Optical Fiber Communication Senior
Satellite Communications Pratt and Bostian
Monochrome and colour R.R. Gulati
Control System
(i) Control System Engg. I.G. Nagrath & M.Gopal
(ii) Automatic Control System B.C. Kuo
(iii) Linear Control System B.S. Manke
Electro Magnetic Theory
(i) Elements of Engineering Electromagnetics N. N. Rao
(ii) Elements of Electromagnetics
(iii) Engineering Electromagnetics Sadiku
(iv) Antenna and Wave Propagation W.H.Hayt
K.D. Prasad
Digital Electronics
(i) Digital Design M. Morris Mano
(ii) Digital Systems Tocci & Widmer
(iii) Modern Digital Electronics R. P. Jain
Computer Engineering
(i) Microprocessor Architecture, Programming & Application Ramesh S. Gaonkar
(ii) Computer Organization and Structure
Stalling
Microwave Engineering
(i) Microwave Devices and Circuits Liao
(ii) Microwave Engineering Sanjeev Gupta
(iii) Microwave Engineering Pozar
Network Theory
(i) Networks and Systems D. Roy Chaudhary
(ii) Engineering Circuit Analysis Hayt
Measurement and Instrumentation
(i) Electrical & Electronic Measurement and Instrumentation A. K. Sahney
(ii) Electronic Instrumentation
H. S. Kalsi

Mechanical Engineering:
SUBJECT AUTHOR
ENGINEERING Thermodynamics P.K. Nag
Cengel and Boles
I.C. Engine R.P. Sharma
M. L. Mathur, R. P. Sharma
Gas Turbine and Propulsive Systems PR Khajuria & SP Dubey
V ganesan
Fluid Mechanics D.S. Kumar ,k.l.kumar, Cengel & cimbala, Frank m. white
Compressible Flow S.M. Yahya
John D. Anderson
Heat and Mass Transfer P. K Nag, JP Hollman, D.S. Kumar, R.C. Sachdeva
Refrigeration and Air Conditioning P. K Nag , CP Arora Domkundwar
Fluid Machinery D. S. Kumar , Jagdish Lal, RK Bansal
Theory of Machines S S Rattan , Thomas Bevan
Mechanical Vibration V.P Singh , G.K. Grover
Machine Design Shigley , VB Bhandari
Material Science WD Callister IP Singh
Production Engg. P. N. Rao ( Vol I & II) ,Kalpkjian Schmid Amitabh Ghosh & AK Malik
Industrial Engg. O. P. Khanna Buffa & Sarin
Operations Research A.M. Natarajan, P.Balasubramani
Strength of Materials Timoshenko gere, RAMAMRUTHAM, B.C. Punamia