Interruptions are a part of life. At home. In the office. In the home office. At the coffee shop. Wherever.
You can't get away from them.
Everything from phone calls, to knocks on the door, to co-workers needing your opinion, to loud children, to cats clamoring for a position on your lap, to your partner deciding to share [quite exuberantly] with you a new and interesting topic he's just learned about.
These interruptions make a convenient excuse when it comes to not writing.
But that's all they are: excuses.
Writers write. And that (often) means writing around, through, and even during distractions.
I seem to recall that I had a much better grasp on writing through distractions when I was a teenager. To my mother's chagrin, I'm sure.
Sometimes I wish I could easily access that selfish mindset that comes with adolescence. Writing is, after all, a pretty selfish pursuit; time consuming, exacting, and internal. As a teenager, I think I was more likely to be pardoned for such a disposition than I am as an adult. Also, in the past few years, I think I may have swallowed some of that societal garbage that says I need to be "less selfish" with my time and attention. ("Less selfish," I often find, translates to: Putting everyone else first. Which is pretty detrimental to your own health and well being.)
Either way, I find it harder, these days, to write through interruptions. But I keep trudging.
And I find that some interruptions are easier to deal with than others.
I can ignore, for instance, a ringing phone or a child playing loudly outside my window. (I've mentioned before that head phones and music are a common companion.)
It's much harder to ignore someone who is physically present in my space and intent on talking to me. (Though I have been known to continue scribbling away while giving monosyllabic answers. What I find amazing is that this doesn't deter some people.)
Since it's probably not a good idea to go around gagging everyone who interrupts your thought process, you have to consider other options to get the fact--that you are not available for conversation--across. Which brings us to: the Writing Hat.
That is, a literal Writing Hat. (That's mine on the left.)
Much like setting aside a specific time or place to do your writing, plopping an actual hat on your head can help you get into the writing mindset.
If nothing else, it serves as a physical sign to other people that you are, in fact, busy (even if all you seem to be doing is staring at a blank Word document or playing an endless game of Spider Solitaire).
Of course, you'll likely have to set aside a moment to introduce the people in your life to your Writing Hat, with a clear disclaimer that when you're wearing it, you're not to be disturbed, on penalty of death, dismemberment, or disemvoweling. (I'm not certain the latter works outside of the written word, but if I'm annoyed enough, I'm sure I could find a way....)