How do I secure a patent on a product I have designed?

There is no next step unless you want to file for a utility patent application. In that case you have until 1 year from the day you filed your provisional application to file your application

I am afraid that your provisional application has expired and you have lost your filing date. If there have been any sales, offers for sale, or publication of your invention, it is too late to file. Regular utility applications need to be filed within a year for a provisional filing date. It is best to hire a registered U.S. patent attorney to draft a patent application. Otherwise, the risk of a resulting patent being invalid and unenforceable is very high. The cost of securing a patent depends on the complexity and the number of rejections received by the U.S. Patent and Trademark Office. In a negotiation session, where the applicant tries to get broad coverage for a wide range of alternatives, and the Office tries to limit the applicant to one specific design, the Office routinely rejects everything and the applicant has to file amendments and responses in multiple rejection/response cycles until claims of a reasonable scope are allowed. The average legal fee for preparing a patent application on an invention of minimal complexity was $7879 in 2009. For relatively complex mechanical, the average fee was $9699. For electrical or software, $13,277. These are just averages. There is also a government filing fee of about $600 for a small entity. The average fee for each amendment/argument was $2322 for minimal complexity (rare) and $3135 for a difficult rejection for a mechanical case, $5021 for an electrical case. You should plan on about three of these rejection/response cycles, though it could take more. To reply a third time, a Request for Continued Examination and another government fee of about $600 is required. In some cases, if an examiner is being particularly difficult, an appeal may be advisable, and an average cost for a written appeal brief was $5547. If a Notice of Allowance is received, there will be an issue fee of about $1000 government fees for a small entity plus a $200 service fee for filling the form and attending to allowance formalities. If these numbers sound high, be aware that the average cost of a patent infringement trial is over a million dollars. With such high stakes, litigators pick apart your patent and seek out the smallest errors to try to invalidate the patent. it is important to have a well drafted patent or there is a risk it will be found to be invalid or unenforceable. These are averages for the U.S. My fees tend to be a little lower than the averages even though I have 20 years of patent preparation and prosecution experience. If you would like a more precise quote, I would require a written disclosure and I can send a form for you to use. Please let me know if I can be of any further assistance. Unless I hear from you, I will assume that you are not proceeding. No attorney-client relationship exists until a representation agreement is signed and an advance fee is paid. Thank you again for your inquiry.