Setting up the console in DoTA 2 is extremely easy. The console is used to input commands that change the game in a number of ways. This could be user interface changes, such as the size of your cursor, or actual game play changes, such as binding a key to a specific power.
In Steam go to the ‘Library’ section and right click on DoTA 2 to select ‘properties’.
In the ‘general’ tab click on ‘Set Launch Options’ and type in ‘-console’ (without the quotation marks) and hit ok.
You now have a working console and can start entering commands right away. Don’t know any? Check out this post for some useful console commands!