I'm 22 years old and I got my first job a couple months ago, the workplace is very informal, even with bosses, we have coffee breaks together, we discuss and joke about things that come up at the time, but sometimes I find myself in an awkward situation.

When we leave the office we usually say "bye" to everybody in the other offices if doors are open. We have 3 offices of 5 people each and one office each for the boss and his brother which is the co-boss.

Sometimes it happens that the boss' door is open so I say "bye" without thinking too much and then I see he's on the phone, so I feel a little awkward and walk through.

How shall I act? Maybe looking inside first and only say "bye" if he's not on the phone? What shall I do if he's on the phone instead, like some gesture or some sort of smile?