I have written numerous documents over the years. I have written procedural, informational, and instructional documents. I have built numerous applications. I would take the official documentation from the vendor and the install documents from the development team and then create my own documentation. More often than not the development installation documents were missing steps or even had errors. Or they didn't include security steps. Or didn't account for various customer customization or requirements. A lot of my old security documentation I cannot place here as it is proprietary information. But I hope to redo my old AIX, VIOS, HACMP and HACMP/XD (now called PowerHA) documents. I also have a number of Linux documents I need to redo.