Does the Raspberry Pi have its own connectors for the 26 GPIO pins? If not what connectors do Pi users typically use for connecting these pins to peripherals?
You have a couple of options:
For a more permanent installation I might use a ribbon cable and etch a custom PCB.
In the end which method you choose comes down to price, convenience, and how much you will be modifying your circuit.
The pins are standard 0.1 inch spacing pins, so you have a lot of options including
Unfortunately every brand has it's own names for these things, so finding them in supplier catalogues can be a bit tricky.