Before you sit down to write, you must consider where you are and what might disperse your concentration and then get rid of the distractions. And I don’t just mean turn the TV off (unless background noise helps you), tell people not to call you during the time you’ve set aside for writing or take the pet out of the room; after all, it’s impossible to write with a purring fur ball on your keyboard. There are other things in your environment that might steal your focus away from your work.
Scented candles or air fresheners?
That might fight the bad odors in your house, but if they smell like vanilla, pudding or a cocoa, you just might take a trip to the fridge once… Twice… Keep going to the fridge when you should be writing.
A nice, relaxing fountain in your garden?
Sure, it might be relaxing, but the running water might prompt you to do your own run.. To the bathroom.
Bottom line: see what distracts you and get rid of it.