I've been practicing deep work since reading Cal's book just after it was released. Like any of the good habits it's a tough one to form and keep but the outcome can be tremendous. Deep work has allowed me crank on https://nanagram.co solo. I do one thing at a time. While I'm doing that task I'm basically disconnected from the world - No email, no messaging, no phone, nothing. I've got 2 kitchen timers on my desk: One set to 60min, the other 15min. I spend the whole day offline alternating between focused tasks for 60min and 15min breaks. I'm constantly surprised by how much I can accomplish with 40min still left on the timer. During the 15min breaks I stay offline. Using this approach of doing one thing at a time I find it's relatively easy to flow from one thing to the next. Unless I crack and get pulled into a network tool :)

For longer, 2-3 day tasks, I completely log off and don't connect to the world until it's done. This means avoiding any network tool through the evenings and mornings until the stretch is over. Easier said than done. Some of my family and friends think I'm weird or get frustrated by my inaccessibility. But they get over it.

After a 2-3 day deep binge like the OP I also face challenges moving from one discipline (say programming) to another (a marketing video). One tool I use is yoga. For a while I had a daily meditation habit going but it's been replaced with 2-3x / week hot yoga. I find it has a way of cleansing my mind and energizing me for the next thing. I also go on fat bike rides to unlock the power nature's constant stimuli has on your mind as Cal talks about in the book.