You are on the right track!

Here are the steps:

1. Press 'Add to Slack' -button in our website or click here
2. If you have multiple workspaces, make sure that you are logged in on a correct one
3. Accept Slacks request to add Evergreen to your Workspace
4. You got redirected to our success page and you can see the amazing gif (below)
5. You received a welcome message from Evergreen
6. And we are done! 🎉

https://giphy.com/embed/l0MYt5jPR6QX5pnqM