The first step in becoming a member of the Sons of the American Revolution is to gather your information about your family lineage, starting with yourself and working backward in history. To help keep track of the names and facts for your application process, the National Society offers a Worksheet which you should download and use:
Naturally, the next step is to contact the Missouri Chapter near where you live. Each chapter has the resources to help you. They know how to prepare the official application form which will eventually be submitted when all the facts are gathered. They may be able to help you with the genealogical work. They will understand well the level of proof documentation that you must provide for each person in your bloodline back to the Revolutionary Patriot. Most importantly, they will offer to sponsor your membership and support your efforts through the application process.
Remember that joining your local chapter is one of the most pleasant parts of joining the SAR.