I'm now almost done with a schematic in Kicad's Eeschema, but some links to the "outside world" are still missing, and I don't know yet how to add them to the schematic, so that they will appear as soldering holes in the PCB later. Here is the relevant part of my schematic:
As you can see, it's all about 7 pins on a microchip (TDA7318 mixer): 3 of them belong to its I²C interface, and the other 4 ones are audio outputs, which shall lead to an amp residing on another PCB.
Now I'd like to know the following: Which parts shall I add to the schematic, so that Pcbnew will add one soldering hole per pin? For the I²C link, I've already added a GS3 connector (sadly without knowing whether this is the correct part). In real life, I would attach a level shifter with a 3-pin 0.1" header here. For the 4 audio output pins, I would simply solder one short wire each, which would then lead to the amp PCB.