I had one or two comments that there was not enough information given as to what should be written into your query letter. I did make the point that there is a lot of nonsense written about the query letter and what one should put into it. The more you put into it all the more formulaic and wooden it will become; the very antithesis of what your would be agent is looking for. Keep it simple. There was little point in me listing 1001 things which you should not include in the document. The few points given in my previous post used in right kind of way is quite sufficient to present yourself in a meaningful way, and catch the eye of an agent.
And now to the dreaded synopsis. I used to believe that condensing your 100,000 word novel down to 500-600 words to be even more difficult than writing the novel. But, of course, that is really not what is required. As with the query letter some creative thought is necessary.
1. Try writing the synopsis in much the same style as the manuscript you present.
2. Limit the synopsis to no more than 2 pages.
3. If your novel is plot driven then describe only the main plot. Do not describe your sub plots. The last thing you want to do is confuse your would be agent, for that would be the quickest way into the rejection pile. And make the writing both logical and interesting. Describing a long descriptive list such as: First this happens and then that happens and then this happens and then that happens may well be logical but it is also seriously tedious. Make your description interesting and to the point.
4. If the novel is character driven then describe the main characters (5 maximum) and show how they drive the plot in the briefest of ways. Show you understand their interaction. Demonstrate that the novel works.
As with the query letter show the very busy agent that you can be creative and give them reason to want to read your sample chapters. The synopsis and the query letter are the only tools you have. Use them wisely.