Anyone can use the Slack app by adding the PushMetrics app to their Slack team as long as this is permissible by their organization's Slack setup, and they are given the role interactor, account owner, or admin. See user roles & access permissions.
If your organization requires an administrator to install applications to your Slack team, you will need to have them help with PushMetrics setup. See connecting to Slack.
Once the PusMetrics bot is set up, and you are given the right user role, you're ready to go.