Basic stages of starting a business:

• Come up with a good business idea
• Make a business plan
• Organise funding
• Select your company form
• Find out which permits you will need
• Notify the Trade Register and the tax authorities of your company
• Make sure you have the necessary insurances
• Organise your accounting

More information on business plan, see here.

More information on company forms, see here.

Source: InfoFinland