If you’re developing video courses, here is a quick summary of 12 principles developed by Richard E. Mayer, which you may want to familiarize yourself with for the best learning outcome:
1. Multimedia – People learn better from words and pictures than from words alone
2. Coherence – People learn better when extraneous information is excluded
3. Signaling – People learn better when cues are added that highlight the key information and its organization
4. Spatial and temporal contiguity – People learn better when words and pictures are physically and temporally integrated
5. Pre-training – People learn better when provided with pre-training in names and characteristics of key concepts
6. Segmenting – People learn better when information is presented piecemeal rather than all-at-once.
7. Modality – People learn better from graphics and narration than from graphics and printed text
8. Personalization – People learn better when words are presented in conversational rather than formal style
9. Voice – People learn better with a standard-accented voice
10. Embodiment – People learn better when on-screen agents display human-like gestures and movements
11. Animation – People do not necessarily learn better from an animation than from static diagrams
12. Image – People do not necessarily learn better by having the image of an instructor on the screen
Also, check out this great lecture by Mayer, explaining his principles.
https://hwpi.harvard.edu/hilt/blog/principles-multimedia-learning-richard-e-mayer