Zapier is a no-code automation tool that enables users to create automated workflows by connecting different apps. The tool offers two options for creating daily reminders in Slack: using a pre-made template or building a custom Zap from scratch. To get started, users need to log in to their Zapier account and set their timezone. They can then choose whether to use the default schedule or customize it according to their needs. Next, they connect their Slack account to Zapier and select the channel where they want to send the reminder message. The user can also add custom data to the message and configure other settings such as sending the message from a bot or auto-expanding links. Once the setup is complete, users can test their Zap and turn it on to receive daily reminders automatically in Slack.