It is helpful for you to put down on paper all your likely sales and expenditure as that way you can see for yourself how much you will need to bring in in cash to break even. You really do have to know how to do this, as the bottom line is the most important thing is business, that and cash flow.
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No you dont need a buisness plan but is a good idea to have one this let you plan on how your buisness is going to grow.
I wish you the best of luck in your new venture
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If you are taking all the work to open up a business, you might as well take a few hours and put a business plan together. It will still help you plan things out.

The biggest thing is to do some research and see what kind of revenue you expect to make in the first few years. How do you plan to compete with other stores like Hallmark, etc? Writing a business plan could save you from starting an unprofitable business before you get started. Be conservative in your estimates…. if it looks like you don’t have a chance of making it, don’t open the business, come up with another idea.

I would say the majority of people who end up going out of business did not write a business plan, definately.

And I think the word you are looking for is sole proprietor, not sole trader.
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If your logic is such that you think you might need a "business plan" to do what you propose then I think you should forget the idea of becoming self employed. Your self delusion will undoubtedly lead to your self destruction.
Have you any idea what a business plan is??
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If you are sure you know all about accounts and VAT, have done your research to se if the business is viable then carry on. They say you never plan to fail, but when you do it’s because you failed to plan!
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If you are unsure whether you need a business plan or what it should contain, it suggests you may not be ready to start your business just yet. Until you have planned it out, you don’t even know whether there is a business to start. It is good to be enthusiastic: It is even better to be enthusiastic and prepared.

You need to think about things like:
What is the market size? What is the competition? What makes me different? How much of the market can I grab – and what makes me think that? Are you aiming for a particular market segment and, if so, how will that affect your ability to carry the right stock? How will I attract my target customers and what will that cost me? Is the market seasonal and, if so, can I be ready for it? How much will it cost to find and equip premises and where will they be? How much will it cost to stock it and can I afford to carry unsold stock (Xmas cards, Valentines cards) for a year … will they even survive? How much are council tax and insurance? How will you deal with banking and how much will it cost you? How much will you pay yourself? What value of sales do you expect each month, looking forward for at least a year – more if possible. How does all this tot up if you do a cash-flow forecast (what you will spend and when and what will come in and when)? When will you break even, how certain is that and what if you don’t? How do you expect the business to be performing in one year, two years, five years …?

That is far from being a comprehensive list but, if you can at least answer those questions, you should have a basis for a business plan. Challenge your own assumptions (How do I know that? What if it doesn’t?). The business plan will at least help you think about the things that are important to your business and will provide a reference point to assess how well you are doing.

As it was once put to me " If you don’t know where you’re going, your chance of arriving is not good." Good luck
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However big or small your proposed business is, you should always have a business plan. If you’re not applying for funding then it doesn’t have to be so complex.

The key things are knowing what your objectives are, personally and for the business, over the next 3 years, what your products are (just greetings cards or other gift-related items, for example), stock levels, suppliers, discounts, minimum orders, the cost of your premises and staff, your projected sales and most importantly, how people will find out about you. You need to do more than just open your door to draw people in.

These are just a few things that every business needs to consider.

Contact Business Link for some free help on writing your business plan and setting up your business.

Good luck!
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Business Link – http://www.businesslink.gov.uk
For more on starting in business visit: http://www.parrexcellence.com

Apologies if you know the following already!! There are loads of sites offering tips and advice but preparing a business plan properly is a very big project and I think that (if you haven’t done it before) you should work your way through a book. Doing it on the web (filling in something) won’t enable you to really get to grips with the concepts involved and allow you to do a proper analysis of the business. You’ll need about 50 – 100 hours I think to do it properly. There are two parts to the BP: the written part and the financial forecasts (spreadsheets). The number crunching is what will make or break the business plan so its essential to understand cash flow, profit/loss, balance sheet etc. Using a book means you can go through these concepts properly before you start trying to use them as tools as part of your plan. A BP can have lots of functions but the main two are: to prove to yourself that its viable: do the numbers add up??? and then to demonstrate to others that no only does the business idea make sense but that you are a person that can be trusted with their money! (you say you don’t need money now, but later you might _money to expand maybe…an investor will want to see how your present set up compares to the original business plan.) This part is often not understood properly: an investor will not give you money if you don’t know how to work out the basic financial forecasts or if you don’t know what gross profit is or what any other basic business/accounting concept is. By working through a book and creating your plan at the same time you get a crash course in these things. (Anyway if you try to run a business without having a basic understanding of these things you will always be feeling your way in the dark) That’s what i did anyway! Blimey didn’t mean to write so much!! I hope thats helpful
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It would be helpful for the future, you should contact a decent accountant, I use these.

Good luck
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http://www.quartaaccountancy.co.uk