This is just a simple advice column. For organization, see your attorney, CPA or tax professional. There are too many types of organizations which have different ramifications in each jurisdiction. Regardless of how you organize your business, whether it be corporation, limited partnership, limited liability corporation, general partnership, joint venture, etc., do it in writing. Keep all records in writing.
Records are important.
This is a very simple procedure. This number will keep all your business transactions separate from your business transactions. It will be your identification on all tax materials. It is free to get and very useful in your business. Check to see if you need a business license in your local jurisdiction.