If you have done a good job with writing papers, putting together the thesis shouldn’t be too hard, but give yourself plenty of time! Ideally, each paper (including any supplementary info) can be turned into a chapter. You then need to add an introductory chapter and a conclusions (or future outlooks) chapter and perhaps an appendix with additional info, experimental setups, etc. It is essential that you write your thesis in LaTex, so you will want to familiarize yourself with it (see below).
Here is an example of an excellent thesis, by Michael Kelzenberg. You can download the PDF at the bottom of the page or by clicking here. Note that nearly all of the figures are very high quality, as are the descriptions and explanations.
A template and instructions for preparing and writing a thesis at the University of Maryland can be found on the IREAP website: http://ireap.umd.edu/resources/thesis-templates.