The setup process is quite similar to that of display ads. You’ll have to create video ad units, line items, and add creatives to the line items. Here’s the complete step-by-step guide.
While uploading creatives for In-banner video ads, you need to make sure the creatives are HTML5 creatives or video native formats. You can either use Google Web designer (GWD) to design a standard HTML5 video creative or use Google native ad templates to create native ads.