Or, imagine you’re in a sales role and have a long list of people who you need to talk to. You write out a checklist of everyone you need to call and every client you need to see, and start prioritizing.
Run through these checklists allocating priorities from A (very important, or very urgent) to F (unimportant, or not at all urgent). If too many tasks have a high priority, run through the list again and demote the less important ones. Once you have done this, rewrite the list in priority order.
But in you’re in an operational role, or if tasks are large or dependent on too many other people, then it may be better to focus on a longer-term checklist, and "chip away" at it day-by-day. Many people find it helpful to spend, say, 10 minutes at the end of the day, organizing tasks on their list for the next day.
You may find it easier to compile several checklists (covering personal, study, and workplace, for example). Try different approaches and use the best for your own situation.