Buying Baby Audio plugins from SOUND7 you will now have received your product activation code at checkout, in your order confirmation email and if you opted to create a SOUND7 account you can find it in your account order page.
If you've not yet downloaded a copy of your plugin then go here and do so for your PC or MAC and Plugins Purchased.
Once downloaded, run through the plugin install process.
Next load up your Baby Audio plugin in your DAW of choice, you'll be presented with a plugin screen very similar to this.
Simply enter your serial, you've be presented with an activation confirmation and you're all set.
Sometimes a plugin restart is required.