Basics
Email (unencrypted): owen (at) owenab (dot) com
Message me on Signal at this link or by entering my username, owenab.314
Messaging
Signal is the gold standard for encrypted messaging and phone calls. You can download it here: https://whispersystems.org/.
You can create a new message and search my username, owenab.314, to contact me.
Signal will keep a record of when you set up an account and what phone number you've used, which can be sensitive information.
One shortcoming of Signal is that it's difficult to use without giving up your actual cell phone number. If you have an Android, you can find instructions on how to hide your true cell phone number here using Google Voice: https://theintercept.com/2017/09/28/signal-tutorial-second-phone-number/.
WhatsApp and iMessage are ok for most things. I don't recommend Telegram, Threema or SMS text messages.
ProtonMail automatically encrypts emails. My address is owenaustonbabcock (at) protonmail (dot) com