Canva is filled with options to make quick, but beautiful, designs.
Each new project can be designed with a template with the dimensions already set, so that can focus your attention on creating beautiful designs in seconds.
Canva has some templates for print materials but not for bookmarks.
Easel.ly is a program for infographics recommended by Librarian Design Share.
Integrated into Google Drive, Google Drawings provides many basic image-related functionalities including:
Powerpoint is the fastest, easiest way to quickly create plasma screen slides--no need to resize images and it's easy to add type and layer it over an image or put it into a text box. Save your file to either .pdf or an image file as per your plasma screen's requirements.