Plan your working wardrobe with pumping in mind: Generally two-piece outfits with lightweight tops (prints can help cover up stains) that are pulled up from the bottom are best for pumping or nursing. If you combine that with a jacket, cardigan, over-blouse or a wrap you can not only nurse or pump discreetly, but can help cover you up if you have a milk stain.
You might also want to look for nursing dresses and tops that facilitate discreet nursing and easy access for pumping. Nursing wear is designed to fit a nursing mother's larger bust size, but maintains non-maternity sizing.
Just to be on the safe side, don't forget to wear thick, absorbent, 100 percent cotton, nursing pads inside your bra, and change if they get moist.
You may find that your milk starts to eject if you've gone too long between feeds, or even if you think of your little one. If your milk feels like it's beginning to spray, quickly fold your arms tightly over your chest, pressing down on your nipples with your forearms. It's doubtful that anyone will know you're doing.