How can I make a redirect script publicly available on a subdomain?

[sanderdame]

Goodmorning,

We are using with a big affiliate site as a partner, but we have some trouble with the tracking of our shopify store.
They suggested to make a subdomain (shop.croom-sanitair.nl) to our main domain (croom-sanitair.nl) and use a redirect script. I was able to setup the maindomain but I have trouble adding the redirect script.

SUMMARY TO SET UP THE REDIRECT LOCATION

1. Determine the server environment and choose the programming language format accordingly (or create one based on one of the example codes)
2. Create the redirect location (either a rewrite, physical directory or subdomain)
3. Set the domainName variable with your main domain (without www.) in the redirect script example
4. Make the redirect script publicly available at the chosen location and if using an actual physical directory, turn off the URL rewrite engine according to your server configuration options
5. Use the tracking test URL that corresponds to the redirect location to test the redirect

Can someone help me with step number 4 of making it available?

Thanks in advance!