Text version:

Inspiration

When a friendly creature within 30 feet that is aware of you fails an attack roll, an ability check or a saving throw, you can Inspire that creature to make it reroll the die.

Limitations. (a) You can only Inspire another creature once per long rest; (b) If you give or receive Inspiration, you can't give or receive Inspiration again until the end of the current round.

Flavour is a welcome addition. When inspiring another creature, you are invited (but not required) to describe how you are doing it: for example, you may hype them up, warn them of an incoming danger, or throw a passing comment that may help them achieve success in a task.

No beggars allowed. Inspiration should feel genuine and come from the heart: this mechanic is meant to incentivize bonding and roleplay, not min-maxing. At the DM's discretion, you lose the ability to give and receive Inspiration until you finish a long rest if you ever explicitly refer to this mechanic, such as asking others to give you inspiration, or making a throwaway comment about it (for example: "Could you please give me inspiration on this roll?", "It would be cool if somebody could help me out on this roll", "Man, I feel really inspired right now", "Don't waste your Precision Attack on this roll, I'll just inspire you if you fail").

This mechanic is meant to replace the original inspiration. Instead of the DM awarding Inspiration to a player, it's the players themselves who help each other during hard times.