There are a ton of tutorials on youtube to help. I recommend checking them out. Here's one for a new user with studio one . To activate just open it, click on 'Studio One' menu item and click 'Activate Studio One' and enter your product key. As far as registering goes, log into my.presonus and goto https://my.presonus.com/products/software. And on the upper right there is an orange box 'Register a Product', choose the type of product and enter it's product key there.