Assuming the patent has been granted, simply quote the patent number as a reference in the manuscript. If the patent has been applied for but is not yet granted, or has not yet been applied for, I would advise against quoting it in a manuscript because of the risk of your own prior publication in the manuscript invalidating all or part of the patent application.
The question that you are asking has two different situations:
1) The patent is already published-you can use the application number or the patent number in that case and most formats APA, MLA, etc. have formats for the patent. A patent citation is like any other citation.
2)The patent has not been published - this situation has two possibilities. The first is when you are either not the inventor or you are the co-inventor of the patent. Under this scenario you have to contemplate the nondisclosure agreement or contractual agreement that covers such scenario. You must provide due notice to avoid possible complications in this scenario.
The second possibility is where you are the sole inventor. Under this scenario you must review the requirements on concurrent/prior publications for the jurisdiction that you intend to apply to. Not following the guidelines will lead to unfavorable outcomes.
I would advise that if you are in this second camp, that you seek professional advise to avoid any negative outcome.