Execute Your Game Plan
This is an element that, believe me, 99% of the players I see out there are not using.
Forming and then executing a game plan is one of the most important things you can get into the habit of doing as a tennis competitor.
First off, because hardly any one else does it, and, secondly, because it gets you going into the match with a very clear (mental) plan about what you and your partner need to do.
When I was playing my best doubles, we never went into any match without some kind of prearranged plan about what we were doing.
Game plans come in two basic forms:
1. As a result of what you have scouted from watching your opponents or know about them previously.
2. You haven't seen your opponents, but you formulate a game plan based on your own game and what you want to do in the match.
Option one is the more powerful of the two because you can discuss specific tactics regarding the upcoming match, but please do not overlook option two.
In many ways this is the most important option because it forces you to come up with a plan to try and play the game how you want it played -- and this is very important. Too many doubles pairs spend too long worrying about what their opponents are doing and ignore their own game.
Think about your own strengths and weaknesses and come up with ways to maximize those strengths -- and avoid the weaknesses -- all in the context of what you know (or find out during the match) about your opponents.
This will allow you to go into a match armed with a mental map of how to find the treasure (the win), and lets face it, you are much more likely to find the buried treasure if you have a map instead of hunting around the island with absolutely no clue where to go.
Your mental strength increases with the clarity that having a map/game plan brings to the table, which is way beyond what most other doubles teams do in preparation for a match.
Never Play Your Opponents
One of the biggest failings I see in many teams is the handing out of disproportionate levels of respect to opponents. I see it all the time.
In reality, you are not playing your opponents when you are playing a tennis match, you are playing the ball!
First and foremost, you have to react to where the ball is going, what the ball is doing and what you are doing to the ball before you worry about your opponents.