End of 2015UPDATE: The basic commands should still work fine, they added the option to start a private lobby, load up a map from the new UI.
HOWEVER THE GAME HAS BEEN ABANDONED.

Note: You can use the "End" key on your keyboard this opens the console as well.
This option will open a console commnad line at the bottom of your screen like so:

Type in the Command like so and press Enter.
This will load for us the map Hijack Dustbowl.

Note: not all maps have every game mode.
Here is a list of playable maps with their all their possible game modes:
CTR_Bridge
CTR_Bridge_Day2
CTR_Canyon
CTR_Canyon_Day2
CTR_Chasm
CTR_Derelict
CTR_Dustbowl
CTR_IceBreaker
CTR_Liberty
CTR_Oilrig
CTR_Rooftop
HJK_Dustbowl
TDM_Canyon
TDM_Chasm
TDM_IceBreaker
TDM_Liberty
TDM_OilRig
TDM_Rooftop
Thrust_Bridge
Thrust_Canyon
Thrust_Chasm
Thrust_Derelict
Thrust_Dustbowl
Thrust_IceBreaker
Thrust_Liberty
Thrust_Oilrig
Thrust_Rooftop

See that the game mode is the first part and the map is second like so "gamemode_mapname"
Here is what the shortcuts mean:
CTR = Capture The Resource
HJK = Hijack
TDM = Team Death Match
Thrust (node control)

For more info about maps and game mode visit:
http://www.2dawn.com/games/ravaged/ravaged-overview/maps
http://www.2dawn.com/games/ravaged/ravaged-overview/modes
Or click the user guide yellow button in your game client

Now you can play, learn the map, learn how to driver switch seat, setup key or change keybinds or settings without getting blasted every second.
Also very good to practice flying the heli / copper.
Since you have no lag.

Note: incase your PC is pretty old or not so powerful. running the maps take more resources from your PC.
Open your console "~" and use the command "Stat FPS"
This will show your FPS on the top right.
Incase you drop FPS a lot and below 60 you might want to lower your overall setting.
If you're already running on everything low and you have around 10FPS all the time.
Sadly your PC is too weak.