What are some guidelines for creating attractive and functional open or closed captions?

DO-IT Factsheet #106

Captioning is usually considered when the video product is complete, if at all. Instead, the production should be filmed so that critical content does not appear where captioning will cover it (usually at the bottom of the screen). Captions should describe all of the visual content, including nonspeech noises. Suggestions for making attractive and functional captions include the following:

This content and more information is from Creating Video and Multimedia Products That Are Accessible to People with Sensory Impairments [1].