The first time you want to use EMMA, you need to request an account for your user. This must be done by Alturos Support. 

Please open a ticket listing which email addresses require access. If others in your team/company also require EMMA access, it is most efficient to request access for multiple users at once.

Once an account has been created for each user, you will receive an email from "Braze", the front-end tool of EMMA where you will need to choose a password. You can then always login yourself via www.braze.com