Wp Intallation confusion

Hi,

Please help me with simple and detailed step b y step instructions; I’m confused. I read a lot before the installation and understood much,but still have some problems. I’m installing the wordpres blog to my shared hosting account -justhost. I want the blog to be the main site for my server. That is if you type in the yrl-www.makesolarpowersystems.com, the blog should come up.J;m not installing in a directory. I used filezilla and uploaded the fikes. Didnt upload them to the public_html folder. Is that a mistake? I think I uploaded to the root. How do I install wordpress so it be the actual site and not in a directory, Then , how or in which file do I upload a theme for the blog. My last question is that I intend to install Jeff Johnson;s free SEO plugin on my blog. Where< in which file or folder, do I install ie in. Please help,thought I understood but seem to be overwhelmed despite all the reading ,educating myself of wordpress installation. I did create a database on my server. thanks much