Get a standing desk for your computer (i.e. a little nested table/box on your desk), stand when you talk on the phone/text/facebook, when you visit and chat to friends, when you iron, wash up, while you read or watch TV.
My standing desk upstairs in a nice and quiet spot.
2 hours a day extra will add up to the equivalent of an hours exercise class during the week in terms of calories and you prevent back pain, muscle shortening in the back of your leg and improve circulation.
Start with 10 min and see if you can stand in alignment without tiring, if not, just being able to stand for 10/30/60 min a day in alignment without leaning onto something or sitting down is a desirable goal. After all, standing using your muscles correctly should be a natural skill everyone has.
Stand with feet hips-width apart and outside of your feet parallel and all your weight in your heels. Ears, shoulders and hips stack plumb over your heels.
If you are interested in learning more about standing and walking in alignment and how to replace exercise with whole-body movement throughout the day, visit Katy Bowman's blog. Her classes and courses are an absolute eye opener.