I have never written a thesis either, however I did write the documentation manual for an extensive computer program.
My advice is the same I have given anyone who has a large project. Make an outline of the project. As you start to add details your thesis will start to fall into place in an orderly manner.
Take Kim(Simonandhallie)'s advice on time management - she is a supersmart lady who is very organized.
Good luck! I hope this thesis makes the best seller list
