Make sure your idea is worth it. I can't find the article now, but a few years ago I read a good review of patent law that basically boiled down to this: "Don't even think about patenting a Million Dollar Idea. It had better be worth a lot more than that to make it worth your while"
I don't think I agree with the advice 100% but it is a good starting point.
There are a lot of reasons to patent something. Not all of them involve suing to enforce a patent.
- You may want to patent in order to increase your value if you are purchased or go public.
- You may want to have patents in order to make investors more comfortable with investing (they may think, "At least we can sell the patent rights if all else fails").
- You may want them to have some basis for a counter suit if you get sued.
- You may want to generate doubt in the mind of your competitor as to what path they should take to avoid patent infringement (provisional patent applications are often used in this way -- they are not published and they allow an applicant to claim whatever they want without review. They will almost certainly not get all they claim but it is uncertain as how much will be limited.)
Another great source of info (especially on software patents) is Paul Graham's excellent essay,
Are Software Patents Evil?
As to documentation, all you really need to reserver your priority date are witnessed signed sketches. You need to make sure that the sketches document the idea well and the the witnesses actually understand the idea (based on the drawing). There have been a number of famous patent cases were the priority date was lost based on the argument that the witnesses could not have truly understood what they were witnessing. Keep that it mind.
If the idea has international application, you have other issues to worry about. The US is "First to Invent." Almost the entire world is "First to File." You need to keep this in mind for priority dates for international patents. You also have a 1 year clock to worry about. Once you have show the idea to an outside person or offered the idea for sale to customer (NDA's complicate this process -- talk to a lawyer), you have 1 year to file or you loose your ability to file at all.
I wish you all the best with your idea.
Joe J.