I once said to my friend that being a writer means one should get cerebral. That entails the endurance of sitting all day long (or standing if you have that standing desk), working alone, without being and feeling lonely because one is much too busy, engrossed with and accompanied by all the intellectual work.
When I write, everything else comes second. That brings the consequence that I ought to entirely disconnect myself from the outer world. It keeps the mind laser-focused. Think only one thing on your mind and do write about it without hesitation, without fear or anxiety that you have neglected other things and people around you. Don’t bother thinking about the chats you can’t reply right away, the texts your parents sent, the phone calls your employer or client did to reach you. All these things can wait. Once again, they can wait. If you say they must wait, they’ll wait. It’s just a mind game. Be the master instead of the slave.
That said, I always try to write offline. Like now, I am typing on my BlackBerry without the mobile network turned on. Or if I find a desk, I’ll sit and work on my laptop without getting connected to the wifi or internet connection so I won’t be disturbed anyhow.