This same setup can likely be used with other email marketing tools as well, as long as you can create custom fields and use these in your emails :-)
I implemented the steps in less than 10 minutes and now I'm wishing I had discovered this years ago. Soooo helpful! Get it (and implement it) asap to get your new affiliates organized for good! I'm super impressed with how tech savvy Welmoed is. I asked her a question and in a matter of minutes she recorded a new lesson that solved my doubt!
Clàudia Orengo from heartmade.es
The solution: email your affiliates their unique link 
Good news: this setup can be done on Zapier's free plan! 