Do you have your to-do list of things all prioritized with date and time slots for each? How do you keep track of them?
My husband uses Google calendar, so we can both see what is going on in our lives. He also uses an Android phone. I use a small paper diary to log in all the important things (it never needs recharging). Other very busy people I know use index cards or sticky notes in various places to track emails to send, phone calls to make, and tasks to execute. One person even recommended David Allen's book Getting Things Done.
However, the bottom line is that all of us have 24 hours a day, and some of that must be taken up with sleep so that we can be functional in the remaining hours. That means we will have to give up doing everything ourselves. Americans seem to have more of a problem with that than citizens of some other countries. Still, musicians all over the world have to make time to practice, learn new music, write letters and thank-you notes, arrange, compose, book gigs (if they don't have an agent), and a plethora of other valuable and important things to do. This is a severe case of juggling, just like my friends who are both teachers and parents--either of which role is a complete vocation unto itself. There is also the problem of being so thoroughly engaged in composing or practicing that you lose all track of time!
Of critical importance is the ability to take a few minutes to sit and daydream about things. Just as it's important for your muscles to have a rest day between days of weight training, you need some time off to recharge between all the things you're doing. Of course, solutions to this are as varied as people! Still, try different ways to make this work for you because you'll be astonished at how much more productive you can be when you're well rested.
I personally have a stenographer's notepad where I can use two columns for things I must do today and things that can be handled later. The later items can have a NW (next week), NM (next month), or TQ (this quarter) annotation, so that they can be entered into my pocket calendar. Studies have shown that writing your lists by hand activates parts of the brain to help you get things done.
Many people also consider it a huge reward to cross things off when completed, which is hard to do on a computer screen. You can also add personal flourishes when drawing a line through an item!
Yes, we're jugglers too, and most of us wouldn't trade our multi-directional lives for the peace and calm of a hermit in a monastery. But creating a little sea of tranquility amidst an overwhelming to-do list can keep us from being harrowed up by the demands of the world and our artistry. Happy PACED living to you all!