On Planets.nu, a Blitz game is a game that was specifically designed to be played quickly. Blitz games teach players how to quickly and effectively build their economy in the early part of the game.
To create a Blitz game, select Game List from the top menu, then select Blitz from the second-level menu, then select the Start Blitz button. This will bring up a menu.
In the menu, select the race for the first player (the second player will select their race when they join). Select whether the game is to be Public or Private, and select whether or not you are playing ("Host Only" means you're not playing). The game will then be generated.
If a private game was generated, a link to the sector will need to be sent to the other player.