Schedulable and schedule with a cron expression or the UI — pick a pattern and see the string.Every day at 2:00 AM
Cron strings are position-sensitive — always verify against Salesforce scheduler docs.
public class MySched implements Schedulable {
public void execute(SchedulableContext sc) {
System.enqueueJob(new MyQueueable());
}
}
// String jobId = System.schedule('Nightly', '0 0 2 * * ?', new MySched());