Your first step prior to making an invention submission would be to obtain a patent. Contact a patent lawyer and the United States Patent and Trademark office. The patent lawyer will help you through the submission process that assist insure that you will be legally resistant to any potential issues. There's a fee, consider this can change, it is best to contact the USPTO yourself. This step protects your invention and idea from getting stolen.
Your next step is to locate a list of companies who accept invention submissions. For example, if the invention is due to cars, then find an auto-related company which is ready to accept reviewing invention submissions. Many of these companies recommend that you patent your idea first. This protects you together with prevents problems for example idea theft from occurring. You can search on the net for potential companies, or call businesses that appeal to you and ask should they review patented inventions.
A great choice for a big company. A great idea might help enhance their profits. They could already have the concept, however you got the patent before they did. This makes a partnership worth taking into consideration. They've got the resources and you've got the concept. Just make sure they compensate you adequately.
So, for those who have an invention, consider making invention submissions to relevant companies. This could help increase your own profits and removes you against the assembly process. Just make sure to patent your idea prior to deciding to share your invention having a company.