Try to arrange to overlap with your exchange partner, if only for a few hours, as both parties will feel more assured if they have been able to meet. If possible it is a good idea for one of the exchangers to meet the other at the airport, although in reality this does not often happen. Arranging departures and arrivals so that they overlap by a couple of hours can make a brief meeting possible, in which case arrange to meet your partners at a pre-arranged place in the airport.
Failing this, make sure that a friend or neighbor who is prepared to act as your home exchange agent, welcomes your guests and is available to help with any problems they might have. She or he will retain a set of house keys and will be responsible for passing two sets of keys to your guests.