Some boats have a fuel cross over line that you can open and the tanks will equalize. Others have a fuel transfer pump in a crossover line. Finally, if you need to transfer fuel but don't have either of the above, you may be able to do it while running depending on how your boat is setup.
If you have a fuel manifold by your Racors, you can open the fuel supply from the starboard tank, close the fuel supply from the port tank, close the fuel return to the starboard tank, and open the fuel return to the port tank. In this configuration, fuel will be drawn from the starboard tank to feed the engine and returned to the port tank. This will equalize the tanks in a relatively short time.
Caution! Never close both fuel return valves while the engine is running even for a moment. Also, don't forget or you will overfill the tank that fuel is being transfer to.