1) Log into your store's Admin area.
2) Go to the Marketing menu
3) Select Banners Manager
4) This is where you manage the banners and track your click acitivity on your banners
5) You can turn off or on any banners loaded to your site from here (green is on and red is off).
6) You can add or delete banners from here
7) It is good to have a few banners from paid adds or to advertise particular products or services on your site.  This is also an easy place to edit seasonal sale images.

Contact if you would like to consider some custom designed banners for your site.