When ds was that young, 2 months, we wouldn't worry about him being in the same room (or in his cosleeper) when we DTD. Its not like we're marathoners or anything
so it didn't bother us. We would usually wait until he was asleep.
As ds grew, we would still try to refrain until he was sleeping. Whether that meant he was asleep on the couch or our bed, it just didn't matter. It would sort of freak dh out if ds was awake
Our son usually falls asleep between 7-8 pm so that was 'our' time.
I do have a dh that thinks once a week is more than enough so we really don't have a lot to coordinate...
But now that ds is a bit more impressionable and its just not quite 'right' to DTD with him awake at all, we're more apt to wait until the 7-8 pm window of opportunity
We have been known to use other rooms, couches, kitchen tables, what have you, to make sure that ds isn't disturbed by our actions
Course, he has woken up while we're DTD but since we're really not marathoners
he is tended to asap.