Step 1

Download the DZSA Launcher at: dayzsalauncher.com

Step 2

Install and open the launcher, and press "Settings" (Right Top)
Select your DayZ Standalone Path (Where your game is installed)
And type in the name you want to use in-game:

DZSA Launcher settings screen
Step 3

Type "Remnant OverPoch" in Filters to the left:

DZSA Launcher server filter screen
Step 4

Click the play button on the server that is white (The golden coloured are sponsored servers).
Then press "Load" instead of "Play". If you are playing for the first time DZSA will download the required mods automatically.
If you press "Load" again your game will start!

DZSA Launcher server load screen
Step 5

You are now in the Main Menu.
Press Character and select a Character you want to play as.
Now click "APPLY".