The side of the court should obviously be discussed before the first point of the match begins. 

If both players are of equal skills, they should just choose the side they feel more comfortable returning from. Otherwise, consider that the best returner should take the ad side for the simple fact that most of the games end with the serve and return on the ad side. Besides 40-15 or 15-40 (when the server and returner start on the deuce side), every game ends on the ad side (e.g. 40-30, 30-40, 40-0, 0-40, AD-out, AD-in). 

Considering the extra pressure that the receiver has to deal with returning at game points, it is a good option to have the more experienced player play the ad side of the court. 

What if one of the players is left-handed; should he take the ad side? 

Answers: 

– Yes, if the left-handed player can handle returning under pressure better than his partner. 

– No, if we consider that this position puts both players with their strong wings (forehands) on the outside. Since the majority of the balls come down the middle, having the weak side (backhand) covering the middle makes this decision a difficult one. 

The left-handed player, playing the deuce side, can bring many more advantages to his team (assuming his partner is right-handed) because:

– both players cover the middle of the court with their strong side (forehands),

– poaching is easier having the strong side closer to the middle,

– covering the lobs is another advantage when having the better side in the middle of the court,

– returning serve is more comfortable considering that smart servers place the ball down the T (which goes to the forehand side of the receiver in this case).

So, the best way to figure this out is by talking to your partner and evaluating your options based on your individual technical and psychological aspects.