At some point you need to stop researching and start writing. You will know when you have done enough research when the same cases keep popping up over and over again. Keep in mind too what the expected length of the paper is. Here are a few points to check off as the writing phase begins:
Writing guides will not only show you how a particular piece of writing (like a Memorandum of Law) is to be arranged, but will also give you some guidance on how to formulate legal statements in your paper.
Use the McGill Guide as a guide. You may have to be creative though as the guide will not provide you with an example of everything you may be citing. Check in other sources as well, such as the journal collection in Lexis Advance Quicklaw. You can search the footnotes of articles from journals which are supposed to be following McGill Guide rules.
Look for someone who can read beyond your arguments. A proofreader is not simply someone to question your research but is someone who can nitpick on your grammar and sentence structure. Gerunds anyone??