8.5 x 11" is a suitable size for creating a flyer or leaflet, which can be found as the flyer (US letter) size in PosterMyWall's various design sizes.
While we offer a wide range of flyer templates, you'll often need to resize a poster or social media size to a flyer. This can be done easily by opening the design in the editor, click 'resize' on the top right of the editor, and select flyer (US letter) under 'Marketing'.
Once done, make your edits to the flyer, add your content, save and download.