DB9 connectors are not exactly breadboard / perfboard friendly. Fortunately, BCRobotics have the answer!
This simple breakout board gives you a simple breadboard / 0.1″ / 2.54mm pitch compatible platform to work with standard male DB9 connectors.
Female connectors will also fit, but the pin numbers will not be correct - grab the female version instead!
Note: This breakout does not include the male connector.