We often spend too much time worrying about and focusing on the trivial things and not enough time on focusing on the important things.
When you approach your PhD in day-to-day life, it helps to spend a few minutes at the beginning of the day looking at your to-do list (or making one, if you haven’t already) and asking yourself what things on it are important and urgent, not important and not urgent, or just plain trivial.
In other words, work out the things on your list that you absolutely have to focus on and the things on there that can either be forgotten about entirely (because they’re trivial) or can wait for another day (because they’re not urgent or important).
Working in this way gives you some wiggle room if you don’t manage to get things done because it shows you what you can quickly cull from today’s list. Importantly though, you make sure that the most important and urgent things get done first.