The biggest mistake is to journal only in reaction to something that is going on, instead of letting it be part of a system.
Make writing in your personal journal part of your everyday routine.
I've tried traditional paper-based journals, a password protected file on my computer and even journaling apps. I've kept journals about my personal life, professional life and even my business. So what should you do?
Both digital and paper-based journals are useful. With digital journals, you can search old entries and never worry about losing anything. With paper-based journals, you're less likely to be distracted from your practice by notifications or social media. I recommend trying both for a week or so and then using what works for you.