Need help adding a docking module to either side of page

I want to include on my site something similar to the ( customize template settings button ) that is shown docked to the left side of the screen when viewing most templates. I want to include a small amount of info like a picture and some words that stays docked to the side of the webpage when you scroll. I would like it to already be expanded when the webpage loads but it can also be closed if needed. I can't seem to figure out how to accomplish this in Joomla. I have no problem creating this in WYSIWYG but I'm fairly new to Joomla and I could use some help.

Thank you

I would suggest to create custom module position inside body element, then use override.css to create some styling for this element and custom html module to put content into it.
http://www.gavick.com/documentation/joo ... -position/

I've completed the first two steps but I'm stuck on the third and most important step.
I'm not very familiar with how to write up html or php and I don't know what I should be writing in the DEFAULT.PHP file.
It sounds like you know what I'm looking for and the custom html module would be perfect that way I can add what I need to. What code do I need to add to the DEFAULT.PHP and where so that I can have the same effect as the attached picture ?

I have linked our documentation about adding custom module position.
But if you don't know html, php and css - it would be better if you would hire frontend developer do to this custom work for you.