Test the footing of your opponents on clay. Assess their ability to slide and change directions on clay by hitting angles, lobs, etc. If you expose or identify a weakness, use short/deep, angle and lob patterns to force your opponents to move and run down shots.
Soft angle and drop volleys are particularly effective on clay even versus opponents with sure clay-court footing. Soft angle and drop volleys, if hit correctly get absorbed by the clay surface. The shot is best set up by isolating one or both of your opponents back behind the baseline.
Be patient and recognize (with the slower bounce) that it may take longer to construct and finish a point. Very often it’s your ability to get one extra shot back in play that defines your success on clay composition courts.
Never give up on a shot. The slower and higher bounce on clay makes it easier to track and run down a shot.
Don’t feel pressured to serve and volley (or return and volley) to start each point. Serving and staying back is a viable option on clay particularly if you have confidence in your groundstrokes. Similarly, delaying your approach to the net on serve return points tends to be more effective on clay. The important thing is to vary your decision to close or not close following the first shot and to not fall into a familiar and predictable pattern.
Crossing and switching patterns are just as effective on clay as on hard-based surfaces and should be a mainstay of all doubles play on clay. Training should focus on the first step to the ball which is more difficult to execute efficiently on clay. Recovery footwork after the shot is another important focus for effective clay-court movement.
Spin can be more effective on clay. It’s easier to get the ball up high above your opponent’s strike zone with topspin and then close and/or drift to the middle to finish the point with a volley or overhead. A hard slice is particularly effective as an approach on clay composition courts.
Focus on getting the first serve in play with a 75% pace serve. On clay, it’s more difficult to win the point outright with the first serve and easier for the opposing team to attack the second serve so the high percentage play is to take pace off the first serve to get it in (and not start the point at a disadvantage). Hit the first serve with more topspin to clear the net with a higher margin and to kick the ball up above the strike zone of your opponent.
As for specific patterns, I like to close behind sidespin chip shots angled short of the service line. Since there is less risk of getting hurt with a short ball, short and deep patterns (drawing your opponents in and then pushing them back) are good options on clay. Depending on the inclination and strength of my partner, I like to stay back with my partner when returning serve and either defend with lobs and off pace shots or rip groundstrokes with pace and/or heavy spin.
Be creative (and have fun). The extended nature of points on clay creates more shot making opportunities and creative options. Clay rewards teams with multi-dimensional, all-around skills.