This a copy of simosimo guide on YouTube 

You should click here to go to the channel, like the video and subscribe!

Below is the information in his Show More section, this is by far the best guide I have seen for a deatiled and easy to understand video.

Published on 8 Jan 2017

A modern tutorial for getting bots working with Day of Defeat 3.1 along with some nostalgia chat about my favourite Half life Mod. Time to dust off that scratched old Thompson and ship off to DoD_Schwetz!

All you need is a few files and a CD copy of Half Life (non steam version)

DOWNLOAD LINKS:

HALF LIFE RETAIL UPDATE 1.1.1.0
http://www.fileplanet.com/57317/50000...)

WON PATCH 1.1.1.0
http://www.moddb.com/games/half-life/...

STURMBOT for 3.1
http://sturmbot.org/index.php/downloa...

And i'm sorry to say, the AUSGAMERS link for DoD 3.1 has stopped working within the week! I literally downloaded it barely two weeks ago, it's only been around since 2002.........typiacl.

Here are some alternate mirrors thanks to AEX10Playz on Reddit. These include ALL beta versions of DoD, and it includes 3.1. The file is 1.3gb so it's not too bad. Not ideal, but there are no 3.1 links anymore! :(

See below for alternate mirrors for the DoD pack download:

MediaFire: http://www.mediafire.com/file/v32b54g... 

OneDrive: https://1drv.ms/u/s!An6uau001qxRazqdZ... 
Google Drive: https://drive.google.com/open?id=0B0l...