Since Twitter focuses on short-form notices, this is good for play-by-plays of events/protests, or notifications for current happenings. The main focus of content on this platform should be quick, concise information that is sometimes funny as the situation calls for it.
This platform is perhaps the most visually motivated of all the options, so it is essential that a cohesive theme is achieved through all posts, and that the focus remains on the visual persuasion of the viewer. This includes text-based or photo-based posts and the structure of captions.
Finally, since Facebook is the most likely to have longer-form posts, it is important to maintain a cohesive visual theme similar to Instagram, but with the addition of more in-depth information allotted by the style of content on the platform. This is a good substitute for website-like information about your cause or campaign that might be easier to find for the common internet goer.