To try out the player size plugin yourself, first download this file:

sar-playerscale.dll

Sometimes Windows may claim that it's a malicious download. That's just because of how it "hacks" the memory of Portal 2 in order to work. It's not actually dangerous, and won't touch the rest of your system.

Now put it in the folder with the Portal 2 game files.
You can find this folder by selecting Portal 2 in Steam, clicking on the settings icon, then Local Files and Browse.

Then, open Portal 2 and type "plugin_load sar-playerscale" in the developer console to enable the plugin. To change the size of the player, use the command "sar_scale_player x", where x is the player size multiplier.


DO NOT USE THIS IN SPEEDRUNS, IT WILL INVALIDATE THE RUN!