Back to the office

I've gained weight while working at home over the past 16 months and have to go back to the office in mid-August. It's too late to lose all the weight I've gained before facing my co-workers in person. Still, I want to establish better habits that will help me eventually get back to my "normal" weight and perhaps even my ideal weight. I lost about 3 pounds during a week-long summer vacation that involved quite a bit of hiking and not many regular meals, but I can't sustain that pattern now that vacation is over.