Several things which I have to attend to when I record:
-move the clock to another room so the "tic/toc" is out of there.
-turn my thermostat down so there's no chance of the boiler going on.
-turn off the fridge-
Also,
-wear a certain fleece top that makes little noise on the guitar
-be careful to place the wire from my headphones in a place where it can't bang against the guitar while playing
-steady my chair so that there's no "creek"
Oh yeah, and take a deep breath and exhale cause I'm not going to be doing much breathing for the next few minutes!