Step 1: Make sure that sellingstuff.com and otherstuff.com are redirected to the same ip address. You can do this through the provider you bought the domain from.

Step 2: Wait for the domains to replicate to global dns servers

Step 3: Test that the domains are correctly routed to the ip. You can test this by typing cmd > “ipconfig /flushdns” then “ping sellingstuff.com” and “ping otherstuff.com” correctly.

Step 4: Open IIS and select the site you added in the sites section. Right click > go to edit bindings. > press add > put sellingstuff.com in hostname and press OK

Step 5: Press add again and enter otherstuff.com and press ok.

This way you can redirect as many domains as you want to a single site.

Additional information : If you are going to use SSL and you have installed it in IIS, do not forget to select “Require Server Name Indication” after selecting Type > https.