Your local library or bookstore should have a selection of helpful books to get you started and build your confidence. A good writing reference will be invaluable; maybe one such as "The Book on Writing: The Ultimate Guide to Writing Well” by Paula LaRocque, Copyright 2003. This is a highly regarded work by a well-credentialed author with an accessible style, and contains a wealth of information and real-world examples to illustrate her guidelines.
You should also check out content and layout of any books you find that are of the same genre as your own. You needn’t plagiarize to acquire useful ideas for working with your own material.
The most critical step is getting that material out of your head and down on paper or computer where you can work with it. Your spelling, grammar and composition don’t matter at this stage; just get the core information transferred to a concrete visual medium.
Once it’s out there you can take time to elaborate on your ideas, ponder the phrases that will colour and convey them best. As any writer will tell you, it’s the rewrites that create a worthwhile narrative.
As a new author you do have a learning curve ahead, but it will be manageable if you find satisfaction in the process of laying out your information. In fact, it can become downright addictive, to the point where you can’t not write or it haunts you!