Ringo's Caravan Rules

Ringo's Caravan Rules is an unmarked quest

Detailed walkthrough
After talking to Trudy about her argument with Joe Cobb, Ringo can be found in the Goodsprings gas station. By way of an apology for threatening the Courier on first meeting, he will offer to teach the game of Caravan. If taken up on this offer, he will give the Courier a Caravan deck and the holodisk How to play Caravan, as well as giving a vague rundown of the rules in dialogue.

After completing Ghost Town Gunfight, Ringo will relocate to the Crimson Caravan Company, but will still offer to teach the game if he has not already done so.