Filing a patent application without the guidance of a registered patent attorney or agent is called pro se filing. The patent application process can be a bit complicated and particular, and the USPTO's Pro Se Assistance Program is here to help! The webpage addresses commonly encountered issues and has resources for inventors. In particular, the Nonprovisional Utility Patent Application Checklist is helpful.
From the Pro Se Assistance page:
A patent application is a collection of documents that conform to U.S. laws, rules, and guidelines outlined in the Manual of Patent Examining Procedure. The specific list of documents and forms depends on a number of factors, including the type of patent application, the protection sought, and the invention itself. The Pro Se Assistance Program makes this checklist of documents and forms available for your use in preparing your application. While not comprehensive, it contains the most commonly required elements to form a nonprovisional utility patent application.
Additionally, on September 12, the USPTO’s Patent Quality Chat webinar series presents “How Can the Patents Ombudsman and Pro Se Assistance Programs Work For You?”