Start by writing your business plan. If you do not know how to do this, work with a small business mentor who will give you personalised advice. if your finances do not allow for this specific help then get a limited amount of free advice from your government advisor such as the Small Business Advisor or the Princes Trust. Although the help be general it will give you a great start.
Writing your business plan will enable you to plan your business in a structured format. It will be a good exercise and help you get a good structured business together for little outlay.
Do not try to jump into a business too quickly. Plan it out carefully and test out your ideas. To the second saying, if no one wants to buy from you then you do not have a business. Start slowly and research your ideas. Pop over to those masters of sales: Amazon, eBay, etsy and fivver and see what is selling, how popular they are and what kind of money things are selling for. If your intended products are not covered here, and most B2C (business to consumer) products are, then research on the internet. You want – types of market (kinds of people that buy), where these people are, how much they tend to pay and who the big players in the market are.
Now hop over to a few forums, blogs and Facebook pages. Track through some big players on LinkedIn and get an idea of what is being asked for and provided in your market area. Try and find a niche that is not being satisfied. If people keep asking the same question and not getting an answer you have a niche.
Set up a questionnaire on a site such as surveymonkey and post it in some forums and look at the answers.
Now you should have an idea as to what can sell, at what price and to whom.
Get yourself set up legally, the last thing you want is problems with the government. So get a business account and keep the payments and costs separate from your own money. Keep financial records, most will be outgoings and could keep your tax liabilities down.
Now test the market on one of the big selling sites, it is easy enough to set up an account. Test, alter and keep testing until you get a viable and interesting product at the correct price.
Set yourself up a website and learn how to market it.
You do not need a partner to set up your company, that comes along when you can afford it. Outsource the stuff you cannot do by doing your research to find a suitable company or hopping over to elance or guru. Fivver will get you some cheap design and marketing.
Start slowly with this one, partners eat up your equity and employees take away your turnover.
Following this advice should see you with a viable company that will soon make a profit. I wish you luck.