Flag glitch shouldn't be too complicated >.>
Not tested, Theory.
1) Make a game room
2) Set game mode to elimination
3) Set wins to 140
4) Press the stand by button on your modem if you have one if you don't use a tool to tap and if you have no tool then unplug your Ethernet cord.
5) Set game mode to CTF press start game
6) Replug Ethernet cord
7) profit