If you work on a windows computer, look for the Task Scheduler in the control panel. Schedule a task every hour that pops up a message telling you to get up and move. Keep a list of movements to choose from. When the alarm goes off, select a movement from the list and do it.
I have things like climb 6 flights of stairs (I'm in a 6 story building), squats, lunges, pushups, planks, dips on my chair or desk, etc. You could write down yoga positions. You could simply take a walk through all the hallways. Whatever works with your situation. I'm surprised how it makes a difference.
Female, 5'3", 49, Starting weight: 163lbs. Current weight: 135 (more or less).
Starting squat: 45lbs. Current squat: 160 x 2