It´s really easy and simple to setup. There are no downloads etc. required.
All you need is:

• Console

If you have trouble opening your console follow these steps:
1. Start CS:GO
2. Options → Game Settings
3. Enable Developer Console → Yes
4. Options → Keyboard / Mouse
5. Scroll all the way down to "Toggle Console" and set a button you´d like.

This is not matchmaking! It will NOT affect your rank!

1. Play
2. Play with Friends
3. Set to "Friends need Invites"
4. Invite your Friends
5. Start a Casual Match
6. Load the map you want to play over the Console
7. Write "exec gamemode_competitive" and "mp_restartgame 1" into your Console

So the first thing you want to do is click the "Play" button followed by "Play with Friends".
Invite the friends you are going to play with and change the permissions to "Friends need Invites".
In the game settings you don´t want to choose Competitive, instead we will choose Casual.
Don´t worry about the map pool, it will load up a random map anyway. We will change the map ingame via console commands!
Now after loading up a random map you want to open your console.
If you have troubles opening your console read the first chapter of this guide "What you will need!"

Type "changelevel" and the map name into your console and hit enter.
Here is an example of how to change the map to Dust 2:
changelevel de_dust2

If you don't know the map's exact name type the following into your console:
maps *

You should be on the map of your choice now. If so you will need to open your console again.
Type "exec gamemode_competitive" followed by "mp_restartgame 1".
This should restart the game and load up the competitive game mode.

More commands:
mp_maxrounds 20 - changes the total rounds being played to whatever you choose
bot_kick - kicks all bots
mp_warmup_end - end warmup
mp_forcecamera 1 - restricts spectator modes for dead players.
0 = Any team. 1 = Only own team. 2 = No one; fade to black on death

Thank you for reading my guide!
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