You probably want to check out this page on the Dev Center which focuses on guidance manufacturers should give to their end-users.
Each of the entries in the table in the troubleshooting guide has links (click on the name of the entry) to an animation demonstrating the flash pattern. These are good examples of showing folks what they might see.
But it’s important to bear in mind, as the doc says, that you may see various patterns run into each other as the process signalled by a pattern can complete before the pattern does, eg. the WiFi connection process. What matters is the pattern showing when the sequence doesn’t end in connection, because that pattern indicates the stage the imp had reached when the connection attempt failed.
Anything specific users are having an issue with?