Basics of creating a business model or proposal (possible tutorial?)

So I will be gearing up within the next few weeks to create my own small business. Legitimate business of course I would not use others invested money on anything that could be deem illegal.

Now The business that I will be starting will be my first, however the type of business or service is something I have been doing for years and only until recent have I seen an opportunity to make a legitimate profit that with a fairly small investment. I have already the knowledge of my industry but also the talent to become a name that is recognised for quality and service. I also have the technical know how and extremely low overhead and a direction I want to take it.

With that said In order for me to start this venture I need funds in order to do this. I will gave about 25% of it covered and the other 75% invested. But I need to have a solid business plan and timeline to keep my investors confident that they will not only get there investment back but the profit as well. I want to have my business proposal 100% transparent and would like to have my books open If thats required.

But what makes a good business proposal? What type of research and information do i need to provide? And what type of return should i offer my investors?

I do not have a problem sharing my business idea at all and maybe I should do that so that this thread could be something of a tutorial for those who are in my position.

Any ways thanks alot guys and i know you may need additional information to help me with this but in the end i want you all to know how serious this is to me. This is something i hope to be succesfull at and be my main source of income or way of making a living for my family.