If you imported a sample homepage and had some sample promo banners, you only need to enable the builder then edit directly on the frontend.
Demo
On Home page builder, click Add New Block button.
On popup list blocks, click "Promo Banner" item.
BANNER CONFIG TAB
GENERAL
Here you can set some general options for your banner as general color, background color or image and some other settings, just select and experient
BANNER CONFIG
Here you can upload banner image, set url when you click on the banner, add text to banner, add button, adjust text's position, color of button,....
After configuring your banner is completed, just click Submit button to save your banner