What follows are some practical notes to myself; they may be useful to you too.

"Multi-tasking" isn't so much of an issue as failing to integrate a multiple activities working towards a common goal. When doing any complex activity—take driving a car as an example—you must take charge of many controls. There's the gas and brake pedals, steering, checking the mirrors, and so on. So in a way, driving a car is "multi-tasking". For a skilled driver, it doesn't feel this way and indeed many actions happen automatically without conscious thought. Why is this? It is from having practiced a number of procedures and being able to seamlessly move from task to task without even enumerating those tasks.

To continue on this driving analogy, we can consider things that can distract and endanger drivers. A ringing cell phone, a pet blocking the driver's view, a blinking indicator light... There are many things that can make a driver perform worse than they can.

In our "work weeks", we can likewise look for things that prevent us from "driving along" in an integrated way. With a car, you'll want to check your parking brake when you start driving. But having checked it, and started driving, this thing should be out of mind and out of sight. Similarly with our workdays, there can be things that are potentially very distracting—consider some site or communication platform that you check. Without giving yourself guidelines about how often you do(n't) check things like email (or in 2020: Slack, Discord, etc) you can easily find yourself sinking a lot of time into checking or mindlessly browsing and not getting much done at all.

YouTube and other sites that give notifications can present similar distractions. Rather than just watching one or two videos you know you want to watch and then moving on, you can find yourself engaging in an extended "web surfing" session, spending hours longer than you planned as one video leads to the next.

Tactics

There are many tactics one can employ to counter the issues describe above. Here are some:

• Schedule activities for a full schedule that doesn't allow for much slacking off; e.g. have an hour-by-hour routine that leaves little room to get distracted if you follow it with discipline
• Turn off/log off of distracting apps after checking them at a time you select in advance—make sure to get rid of notifications too
• Intentionally quit or postpone projects (including engaging in "social" activities like playing online games) that are out of control
• Find accountability to keep you on task

Work is hard enough already

It should go without saying that you should cut out any counter-productive behaviors. If you are accustomed to eating a giant lunch that makes you feel sluggish and get distracted, this is an issue that you should address. If you are cluttering your workspace such that you have no space to do what you need to do, then it may be a good idea to invest a bit of time in improving the organization of your workspace before pushing yourself with a demanding schedule.

When alone, give up notions of self-indulgence and instead focus on how you can train yourself to do better. When possible, reserve enjoying activities like eating and drinking nice things to when you are with others—in doing so, you can simultaneously work on building enduring connections with people around you.

I have done stuff like drank beer while playing video games for many hours during a day where I didn't get much else done. Do not have days like this—your time is more valuable.