Join an inventor’s association or club, Attend their meeting and seminars. Talk with other inventors who have been through the process, you will find them very willing to help. This will help you avoid common mistakes and those people, companies, and internet sites who are there solely for their profit from your idea.

Perform market research. Is there a market for your product? How will you go about marketing? Should you license your idea to someone else or have it manufactured yourself. These are very important questions you should ask before proceeding further.

Visit the U.S. Department of Commerce’s United States Patent and Trademark Office (USPTO).
Learn as much as you can about obtaining a Patent. Yes, it is possible to file for a patent yourself. However, there are many loopholes and pitfalls so we strongly recommend that you find a registered patent attorney or patent agent, 

Prototyping. There are many forms of prototypes, these range from crude cardboard models, computer-generated proofs-of-concept to fully functional devices. You may be able to make a prototype yourself or have it made by a prototyping company. A good prototype is important if you intend to license your product or have it manufactured and market it yourself.

Marketing is a very important part of the invention process.  Many great inventions have failed due to poor marketing. In this day and age, there are numerous options for marketing your invention.