As someone who one day wants to open up his own business, what are some general tips for creating a good business plan?

Go to score.org and search on "business plans." There are specific questions you need to answer in each business plan, including target market, price points, competitors, marketing and financing. You will need to research each topic to answer the questions.

I have my own business and I got three sources of invaluable help when I started. First and most important were my mentors. They continue to help and they've become something like a company board of directors. I wouldn't think of going against their suggestions. I use The Service Corps of Retired Executives (SCORE). They're available all over the US. Do a web search for them.

Second I found a resource that asks very basic questions and builds an excellent business plan - recommended by my SCORE advisors. It's StratPad and the basic version is free. It's really superb. Example questions : Who are your preferred customers? What do you offer that your customers are willing to pay for? How are you different from others offering the same thing or serving the same need? And so on.

Third and very important I found a source for sales leads. In my case I am an engineer providing design for small projects, home renovation and emergency structure repairs. My lead source is HomeAdvisor.com. I could also have used Angies List. Home Advisor charged me $29 per lead and I converted about 1/3 of the leads into paying customers. So $90 per client for that service. After a year I was able to drop them because I had my work capacity maxed out through word of mouth referrals and I was turning down almost every new customer from Home Advisor.

That's a basic principle. You can determine the scope of your product or service or you can walk away. But once you agree to do business with your customer you must forget the investment and do everything necessary to deliver on the customer's expectations. It's their decision if you are done with the transaction. Stick with them without changing your price, be prompt and available. Make certain they would choose you again. The adjustment on your price and effort can be made on a future transaction. Thr exception, when you can change price and your promised delivery, is when the customer makes a significant change in what they need you to do. I just increased price and got more time for a site drainage plan, when the customer changed the building footprint and added a walk out basement rather than underground. It was a necessary change but I 'll get fair payment for the extra work.

I hope this helps.

I suggest you read Running Lean by Ash Maurya. It's a step-by-step process for defining and testing your business idea. http://www.amazon.com/exec/obidos/ASIN/1449305172

This is what I think will help you:

Look up people who do what your inspired to do!

Look up current fashion trends, and then work on project the next best thing (this can come from old fashion or create new fashion ideas spun from older line fashion)

I am sure your run well with this project, enjoy!

Personally will recomend you read carefully this article its awesome:
http://www.dummies.com/how-to/content/set-goals-and-objectives-in-your-business-plan.html