To add your own link to Lasso (including Amazon products), just click the button at the top right that says "Add New Link."
Paste or type any URL and hit "Add". Congrats! You now have a Lasso Link.
Then you'll see the Link Details page where you can customize your link: Name, Cloaked Permalink, Image, and more.
This is the first step to getting started with Lasso! To learn more about the Link Details page and your link settings, check this out.