It is good you have got a business idea; it is also great that you have got the determination and capability to get the business going. However, you are not ready to incorporate a company yet as your business has not grown to your desired level and you only want to start small. Breaking news, you are wrong.
The very first thing you must do when you have got a business in mind is to make it a separate legal entity and if it has anything to do with intellectual property, register that patent or trademark and here is why:
1. COMPLIANCE WITH THE LAW
You do not want to start off your business on an illegal footing. There are some businesses you must not commence without having registered a company and there are some factors that must be considered in registering these companies. For example, according to the COREN Amendment Act, you cannot run an engineering company without registering it with CAC and supplying the qualifying certificate of registered engineers. Non-compliance with this makes you liable to a criminal provision. That is one out of many of such businesses. My advice, do not take chances and register that business immediately.

2. ACCESS TO LOANS, GRANTS AND FUNDING
You will hardly gain access to loans and funding if your business is unregistered. No corporate entity would give loan to a man/woman that does not have a basic structure- an incorporated entity. Also, obtaining a government loan is near-impossible for an unregistered business. An unregistered business is also shut out against international grants. For those who think they can rush their incorporation when they will need it, this is a big gamble as getting a company certificate in haste is not a sure thing.

3. EVIDENCE OF CREDIBILITY
It is a usual requirement from foreign companies who wish to partner with Nigerian nationals that they have an incorporated company, that they are shareholders and directors in same and that the company has been in operation for at least 2 (two) years. Having your company incorporated for a long term is an evidence of business credibility.

4. BUSINESS BRAND AND IDENTITY
Incorporating your company makes your company a global brand and gives it a global identity. This will affect the overall outlook of your company and will also affect your bargaining power and eventual progress.

5. SEPARATE CORPORATE ENTITY
This is one of the biggest gains of incorporation. Incorporating a company makes it a distinct person in law and gives it a separate legal personality from its owners. Hence, the company has a life of its own and can continue after the demise of its owner. It can take a loan in its own name and can be co-owned by investors. An unincorporated business does not have this privilege.

I believe the fact that you must register your business right upon commencing same is no longer in doubt. To go about registering your company the right way, kindly same me a dm and we will take it up from there.
We will do a sequel on the types of company and what types of company fits your business shortly. We will also discuss how not to incorporate your company.