The "Advanced Floating Content" plugin, allows you to place a banner or video in any of the four corners of your website. Top Left or Right, and Bottom Left or Right.
First, you will need to login to your WordPress dashboard, install and activate the plugin.
To the left of your dashboard you will see the link where you can "Add New" floating content.
For this demonstration, I am grabbing my affiliate code for this particular banner, from my Wealthy Affiliate banners area of the affiliate section of the website.
Once you have clicked the add new link, you will see a form where you can paste your banner code.
If you are adding a video, then your video code would be placed here instead.
Be sure to paste it the "Text" area tab and not the "Visual" area tab.
Add a title so that you can recognize the add once you've created it.
In the floating content details section, you can select to have the banner (or video) placed at the top, or bottom of your website.
You can also choose to have it placed to the right or left of your website.
I typically like to place my banners in the bottom right corner of my websites, I have found this location seems to produce better results for my needs.
In the width section, you will need to add the width of your banner, in pixels or you can add it in percentage. This allows you to resize the banner so that it is not too large or small.
The size of your banner should be determined on a site by site basis, with design and prominence being factors for determining the size that looks most pleasing on your website.
Once you have configured the as, click the "Add" button to add the banner to your site.
Here's a screenshot of my site, as you can see, the banner has been placed in the bottom right corner of my website.
This banner will "float" as a user scrolls to read my content, and is can be easily removed by the site visitor.