Sendible allows you to use the service for 30 days at no charge.
To sign up for a 30 day trial, select Start your 30 day free trial. You will then be asked to add details which can be seen below. This screen will indicate when your 30 day free trial comes to an end.
On completion or during your free trial, you will be able to upgrade to one of Sendible's paid plans.
After creating and activating your account, you will receive an activation email. After activating your account, you will be able to sign in.
After signing in, you will be taken to the Message Box.