If it's not already done,
Paste it on /SteamApps/common/Counter-Strike Global Offensive/csgo/cfg/
On CS:GO, click on Play -> Offline with bots -> Competitive
Pick a map
then click Go -> No bots
Once you have selected a side, open the console command and type exec sothatwemaybefree.cfg
Everything you need to know is explain in console.
Activate the console in Help & Options -> Game Settings -> Enable developer console. This will then allow you to open the console using the tilde key (~ or ²).
Go on your Steam library, right click on CS:GO -> Properties -> Define launch options. Add -tickrate 128.
Start your server and type net_graph 1 on console command. Now, just check values of up and cmd. To hide thoses informations, use net_graph 0
Type exec config.cfg on console or restart your game.
Sothatwemaybefree.com works well with Steam Browser, so instead of Alt-Tab, you can just toggle the Steam Overlay.