How to use Nostr in 30 minutes http://www.youtube.com/watch?v=AiW1zttyblU by theBTCcourse
How to Use Nostr: Top 10 Tips and Tricks by Rhett Reisman http://www.youtube.com/watch?v=7hgZFS5K6kA
Nostr Explained Visually for Beginners by Rhett Reisman - Level Up Your Brain http://www.youtube.com/watch?v=kifwECtwjJQ
Get started with nostr in 5 min by Majestic http://www.youtube.com/watch?v=T1-We1bi_P8
In addition to watching these videos, I did a few other things to improve my proficiency/navigation skills with the nostr protocol:

Read the Nostr documentation on Github: This is a great way to learn about the core concepts of the protocol and how it works.
Join a Nostr community: There are a number of online communities where you can connect with other Nostr users and learn from their experiences.
These communities range from a variety of topics and niches
Experiment with Nostr: 
The best way to learn is by doing. Try out different features of the protocol and see how they work.