Scheduling a daily SMS reminder on Linux, MacOS, or Windows is possible using various tools and platforms. For Linux, cron can be used to automate tasks, while for MacOS, launchd allows users to create daemons that run at specific times. On Windows, Task Scheduler provides a graphical interface for scheduling tasks. Each platform has its own set of instructions and requirements, including setting up environment variables, working directories, and output files. Users must ensure their scripts are configured correctly and troubleshoot any issues that may arise during the scheduling process. By following these steps, users can automate tasks and receive reminders on a daily basis.