Staring at your to-do list, you'll likely go for the tasks that are on the easier side, perhaps the ones that are more fun and don't require any heavy-duty thinking. It's procrastination at its finest -- putting off the harder (and probably more important) tasks for later. However, you're overall work experience will be heightened if you do the hardest tasks first.
Behavioral scientists have shown, in many instances, how an experience can be optimized if the most painful parts occur early on. The reasoning for this is simple -- we prefer when an experience gets better over time, not worse. If this is how your days goes in general, you'll remember it as being a good day and will leave you feeling happier -- simply because your day got better over time.
On any regular workday morning, analyze your to-do list and identify the tasks you dislike and tend to procrastinate on. Then start your day by doing said tasks. You'll have them out of the way and your day will begin to improve immediately after.
The same principle applies to long-term projects or even starting your own business. The hard work done early on pays off later and gets you closer to achieving your goals. So, do the brunt work early on. Not only does it help tackle your procrastination, you'll enjoy the experience more for doing it.