Understand the way they feel
Acknowledge their feelings. No matter how well you've prepared your kids, there will be an occasion (or 500) when they pitch a fit as you leave for the office. (In my house, it usually occurs when I'm running 25 minutes late or distracted about a big meeting I have that day.) When this happens, take the time to validate your child's feelings, and then focus on a solution. "You can say, 'I know it's really hard to say goodbye. Let's think about what we're going to do when I get home tonight. What would you like us to play later?' Then take out the supplies or toy she mentions so she has something to look forward to," says Braun.
Put your goodbye on repeat. Come up with a short ritual that you follow before heading to work and do it every day before you leave. It can be as simple as a "See you later, alligator" or as elaborate as two Eskimo kisses, a bear hug, and a high five. Avery has devised a little custom where I pretend to leave and then come back for "one more kiss" at least two dozen times -- a process I don't recommend since it often requires at least one outfit change, thanks to sticky fingers and juice dribbles. "The regularity and predictability of such rituals help your child feel in control," says Braun.