Consider Slack App is published in the Slack App Directory. You must have the appropriate Slack privileges for installing apps in your Slack workspace in order to proceed.
First, sign in to Consider and go to Settings › Slack Integration page.
When you click Add to Slack, you will be asked to grant to Consider Slack App, only those permissons which are required for the app to work. Click Allow.
When installation completes, you will see the following message.