You need to be deliberate. If you set yourself up with tools without understanding this can leave you not knowing how to use the tools.
See also 20 Rules of Formulating Knowledge.
I've structured this post expecting a reader to drop out at any stage and still get value. Automation lets you slip into a focus state straight away but is specific to what you have on hand.
> “Be like water making its way through cracks. Do not be assertive, but adjust to the object, and you shall find a way around or through it. If nothing within you stays rigid, outward things will disclose themselves. Empty your mind, be formless, shapeless, like water. If you put water into a cup, it becomes the cup. You put water into a bottle and it becomes the bottle. You put it in a teapot it becomes the teapot. Now, water can flow or it can crash. Be water, my friend.” --Quote from Bruce Lee Striking Thoughts
## Level 1: Technique
The Pomodoro Technique uses a kitchen timer to break work into intervals. The default is 25 minutes in length separated by 5 minute breaks. Wikipedia 
The idea is simple. You set a goal, guess how many half hour slots it needs, then focus. When the timer is up, give yourself a 5 minute break.
Timer, Goal, Plan, Focus, Break.
Over time you'll notice two things, the first is that distractions do crop up and your estimations start getting more accurate.
Distractions are fine, noticing distraction allows you to decide "do I want to do this right now". Sometimes it's best to wait till the end of your 25 minute session, or it requires a focus session of it's own. They are neither good nor bad, it depends on your goal.
Improving estimation helps you approximate the value of your time. Other people will love you for this but there is also a thrill when you start getting accurate.
## Level 2: Tools
I use 3 tools in a Pomodoro: A blank piece of paper, the "do not disturb" setting, and a timer called "Flow".
A blank page is important to focus your mind. Write down a goal: what is the most important thing to get done right now? Write it down. Break it down further, how long will each of those tasks take? Take a guess and round up to the nearest half hour.
Setting "Do Not Disturb" is important. Push notifications are distractions that stop you getting into the deep work. Setting "Do Not Disturb" is a decision that lets you come back to those alerts when you're ready. On OSX make sure you turn on "Share Across Devices" so that neither your iPhone or Mac can ping you when you're focused.
I use a timer called "Flow" because of its simplicity. It plays a bell when time is up, lets you glance at the time left on the clock, and has Pomodoro timings already set up. Fewer options means you can dedicate your time to getting stuff done.
## Level 3: Automations
There is a program in IOS and OSX called Shortcuts. It's all about creating groups of actions with conditional actions. If you're signed into the same account then your shortcuts sync across devices.
I've created a basic automation of the processes above and called it "Pomodoro". Focus feels effortless. Starting a session sets Do Not Disturb for 25 minutes and start a Flow. Notifications come back during the 5 minute break and I can catch up on the universe. Shortcut
Pomodoro Shortcut in OSX. Shortcut
Once set up, you can start by opening Spotlight on OSX with <Apple>+<Space> and typing "Pomodoro".
Tripple Tap configured to trigger the Pomodoro shortcut in iPhone.
Those shortcuts sync to an iPhone which I have setup to trigger when I tap the back of my phone 3 times. Set this through Settings > Accessibility > Touch > "Back Tap" and setting this to "Pomodoro".
## Conclusion
Being deliberate about what you pay attention to will help you get stuff done. The techniques, tools, and automations can help you get into a state of deep focus.
Don't let your tools decide how you spend your attention, be like water and you can do anything.
## Appendix
In the last few years I've been using Apple gear so these tools will apply directly to that ecosystem. If you use something else write it up and get in touch. I would be thrilled to link it here.