Draft a business plan
Estimate initial upfront costs: including location renovation costs, equipment and materials, lawyer/accountant fees.
Estimate operating costs: rent, utilities, payroll, non-durables, lab kits, Rx.
Estimate revenues: your number of patients over time, and set revenue goals per month.
Using this information, determine how much money you must spend before you break even.
If you need a loan: do your research
Check out this comprehensive review of physician loans.
Determine what business structure is best for your needs
Some options: limited liability corporation (LLC), professional LLC (PLLC), professional corporation (PC), S Corporation, C Corporation. You'll likely want to confer with an accountant to make this decision, preferably one who has worked with independent medical practices before.
Select a name for your business and check its availability
The name doesn't necessarily have to be the same as the name of your practice.
Most states have a tool on their business center website that lets you check name availability.
Draft an operating agreement/bylaws for the company
This document details the members' business interests and ownership shares, their rights and responsbilities as members, the allocation of profits and losses, and other protocols for managing and operating the business.
Here is a sample Operating Agreement for an LLC.
Here are some sample bylaws for an generic corporation.
When actually drafting this agreement, you and all partners of the practice should meet with a small business lawyer.
Consider finding a registered agent
The role of a registered agent is explained in this video.
As long as you're capable of receiving mail at your practice's address, it's easy enough to be your own registered agent. But in some cases - or if you just want to play it safe - you may want to find one.
Register the business through your state
This can usually be done online through your states business center - just Google "[state] business entity formation". You'll need your Articles of Incorporation/Organization.
Apply for your Employer Identification Number (EIN)
The EIN is like the Social Security number for your business. It's the number the IRS uses to identify you. You can apply for one online here - it's painless.
Open a checking account for your business
You'll likely need your business's EIN and Articles of Incorporation/Organization. For an LLC, some banks may also require a copy of your Operating Agreement.
Establish malpractice insurance
You might want to involve an independent broker that is familiar with direct primary care, or at least private practice in general.
Consider completing a small business workshop
Check your local college for cheap courses or search for an online course. Sometimes a certificate of completion will convince a bank to give you better rates on loans.