Owner needs to select the team
To subscribe, make sure you're the owner of the Trello Team.
Then, log in on http://elegantt.com/account.
In the "Plan" section, you can select the team you want to subscribe with:
Owner needs to select a number of slots (or "subscriptions")
Once it's done, select for how many slots (aka "subscription").
You need to buy one slot per user in your team. For example, if you have 2 team members (including yourself), you'll need to get 2 slots:
The monthly plan : your Trello team members will automatically be added to your subscription when they start using Elegantt.
More information at http://elegantt.com/pricing