Over the years, I have developed a routine that I follow every day. I thought it might inspire some of you.
I wake up around 6:00 to 6:30. No alarms. I have to wake up by myself. I have breakfast around 7:00. I workout for 15 to 30 minutes. Before going to work, I try to find the three most important tasks to be accomplished that day.
Mornings are quiet. I focus better and accomplish more in the mornings. So, I try to cross off as many tasks as I can before going to work.
I don’t do multitasking. Multitasking is poisonous. I do one thing at a time.
I always prioritize. I live by the words of Mark Twain, “Eat a live frog first thing in the morning and nothing worse will happen to you the rest of the day.” 
Both at work and at my personal life I apply inbox zero rule.  If there is any email pending in my inbox, I do three things. I either reply to it, delete it, or delegate it. Subsequently, if I am done with it, I archive it.
Whatever I do, I try to focus as best as I can. To do so, I try to remove all the clutter, and all distractions while I am working. This is the only way I can work on what really matters.
I work in blocks and use the Pomodoro technique, which helps me focus on the current task.  I try not to interrupt what I am doing until I finish. You will be amazed to see how much you can accomplish if you give yourself to a task for 20 minutes without any distraction. This motivates me a lot and keeps me sane. I turn work into a game by working in small bursts and completing one task at a time.
I do not like eating alone. I always eat with friends and colleagues. This is a great way to connect with people. Talking about small stuff, ideas, projects helps you catch up. It doesn’t matter how busy you are. After all, we all eat.
I prefer eating out, whenever possible. It is refreshing and helps me clear my mind.
For taking notes I use a squared Moleskine notebook and a black pen. I developed an adaptation of bullet journal.  I try to save every bit of useful information. It is always surprising to see something you already forgot when you go back to your older notes.
For years I used mobile or laptop to take notes beside paper notes, however it became painful to manage these notes without a proper structure. So, I developed a framework to manage the notes I take. Mobile note-taking is great. But at some point it is either rude or not convenient to use a laptop or a mobile phone to take notes. People would think you are sending a text or just checking email if you are in a meeting. So, I started carrying a small notebook with me. Although it is not always very easy to carry an additional notebook with you, it became essential for me. Especially, I keep it bed side. You can’t know when ideas would come.
I use Evernote to jot down any piece of ideas. I use it whenever possible. From all my devices. I digitize any physical stuff as best as I can to avoid clutter and save them to Evernote.
I use GitHub for all my projects, even for my writings.
I love writing. I use ZenPen web app for writing and use a markdown editor for editing.  It is simple, and looks great. I use LaTeX for academic writing or whenever I need something fancy looking. 
I read articles via RSS. I do a little bit Twitter. I don’t do Facebook.
I use a Pomodoro app, a very minimalist one, which just has a counter.
After dinner, I continue working. Before I go to sleep, I have a short workout session, which is no more than 15 minutes. This way I feel refreshed and keep up working.
I review my notes before I go to sleep. Both the paper notes I have taken during the day, and the digital ones. I try to clear my inbox and take the necessary actions for each item.
I plan the next day after reviewing my notes. Knowing what to work on next lifts a heavy weight on my shoulders.
I try to do one thing for me no matter how tired I am. Reading a book, watching a TV show or writing is among my favorite things. This is very important for me and I try to keep it that way.
Thanks to Kevin McKeown for inspiring me to write this, and Evrim Doğanyiğit, Aykut Aras, Mehmet Kordacı and Christopher Elwell for reading drafts of this.