1 is the first thing that happened. Flashbacks go by when revealed in the Episode not timeline wise. You place all 195 cards in the right order, one at a time. You start with three lives, and ten right in a row wins a lost one back.
The Walking Dead Plot Events (TWD S1-4) is a free ordering game you can play right in your browser, with no sign-up and nothing to install. Every card hides where it falls in the sequence, so the whole run is really one big sorting puzzle. The first card comes up face up. After that you slot each new card into the spot where you think it belongs, and its value only shows once it lands. A wrong guess costs one of your three lives, ten right in a row wins one back, and the run ends with whatever you had down when the last life goes.
Here are 28 of the 195 cards you might be dealt, with 167 more in the deck. Their values stay hidden until you place them.