# As per the thesis format, i want chapter heading at center and also want to define font size for the chapter, sections, subsections

\documentclass[a4paper,12pt, twoside]{report}
\usepackage[margin=1in]{geometry}
\usepackage{setspace}
\onehalfspacing
\usepackage{graphicx}
\renewcommand{\baselinestretch}{1.5}
\begin{document}
% Content starts
\pagenumbering{roman}
\chapter*{Declaration}
declaration goes here

\chapter*{Acknowledgements}
\begin{abstract}
I hereby certify that the work which is presented in dissertation entitled,  in partial fulfillment of the....
\end{abstract}
Acknowledgements
\tableofcontents
\listoffigures
\listoftables

\input{Abbreviations}

diabetes mellitus etc etc
\pagenumbering{arabic}
\input{Ch1_Intro}
\input{Ch2_Literature}
\input{Ch3_Prob.st.}
\input{Ch4_Methods}
\input{Ch5_Results}
\input{Ch6_Future}
\end{document}

• Welcome to TeX.SE. If you need 1" margins all around, why do you load the geometry package with the options left=1.5in,right=1in,bottom=1.5in,top=1in? – Mico Jul 5 at 13:06
• actually for binding I left margin of 0.5 inch. With this code the headings such as ''Abstract", "Declaration" are at atleast 2 inches from the top. How do i solve it? – Sakshi Bhonsle Jul 5 at 13:23
• If you need binding offsets, the margins should definitely not be "1 inch all around". Please clarify your actual formatting requirements. – Mico Jul 5 at 14:12
• I did. Can some one help with this? – Sakshi Bhonsle Jul 5 at 14:52