I missed three performances early on in my career before I realized how important keeping an accurate schedule is. Without a detailed calendar of your activities, days fill with unimportant tasks for lack of plan, and you can never quickly commit to anything without the risk of double-booking yourself. If you're a musician, this can easily become the downfall of your career- booking gigs quickly and accurately is vital to getting call backs.
Even with a great calendar system, it's easy to make simple mistakes that can royally screw up your day. Here's some simple ways I've managed to avoid disaster:
1. Add Drive Time
Your schedule will not be truly accurate until you add your drive time to the beginning of your event. Don't guess on how long your commute is-hop on google maps and plug in your starting and ending address to get an accurate drive time estimate, and then save the URL to your calendar, if you're using an online calendar like Google Calendar, or Apple's calendar app. This way you can simply click the link on your smartphone, and get instant turn-by-turn directions.
2. Add in Buffers
One of the most common issues I see with people who heavily schedule themselves is not having enough extra time built into the schedule. There are always going to be moments where you have to handle something immediately, which can then screw up the rest of your pre-scheduled day.
I generally leave around an hour of times each day free, for all kinds of little things that occur that I can't predict. That way, I don't have to feel guilty about taking a few minutes for an important phone call, or to just relax.
3. Have a Catch-All Day
Since I always use a task list with my schedule, I often find that there are tons of things each day that I can't finish. I used to get stressed out when I felt like I wasn't accomplishing everything I'd planned to do, until I learned a trick that changed everything.
Leave one day, or one time block of 3 to 5 hours each week empty, for all the little things that pileup each week that you need to do, but don't have enough time to finish on any given day. If something isn't urgent, and you get to the end of the day and don't have enough time to finish it, move the task on to the next day.
After repeating this process for an entire week, there will be quite a list of tasks that you haven't finished. Lump them altogether on the final day of the week, and use the extra time to get them off your todo list forever.
Try not to put any task off until the following week- If the task can't be accomplished in one week, you might need to break it into smaller sub tasks, anyway.