Honestly, Scouting Ninja sums it up pretty well if all you're doing is releasing a product on Steam:
1. Form your company or sole proprietorship if that kind of thing is legal in your territory
2. Set up your bank account
3. Comply with all of Steam's developer requirements and conditions
4. Submit game
5. Wait
6. Wait
7. Profit.
But I also routinely perform "legal audits" for clients (both when I've formed the company on behalf of a client or when I'm setting them up for an equity or asset purchase), which generally includes the following:
1. Entity formation and paperwork (register with relevant Sec. of State or territory, OA, bylaws or other organizing documents, board/shareholder/member consents, first meeting minutes, EIN if applicable, etc.)
2. Intra-company agreements (Employee Incentive Plan, employment agreements, employee handbook, PIIAs, shareholder agreements for founding members)
3. External material agreements (EULA, Privacy Policy, third party content licenses [e.g. software, open source, etc. EULAs], contractor agreements, distribution agreements, console SDK agreements, insurance, HR management service and other vendor service agreements if applicable)
4. IP rights management (product clearance [assets and music], TM filings, Copyright filings, patents, PIIAs and NDAs)
5. Financial statements (Confirm GAAP compliance if required, P&Ls, annual reports)
6. Investment paperwork (where applicable)
The list goes on. There is a lot that goes into actually owning an operating a business if you're going to do it right. When you're in a place to make a serious go of it, I strongly advice you first find a great accountant and a decently honest lawyer.
Best of luck!
