I am trying to make a footprint for a PP3 Battery Clip but I don’t really know where to begin (particularly with dimensions). Design something sensible for the two wire solder connections of the PP3 Clip, where the wire diameter is 0.5mm.
The image below is roughly what it should look like.
I am not clear if you are simply connecting a PP3 type clip with flying leads to the board or trying to mount a specific battery connector on the board? If you are simply connecting two wires, you can use any suitable wire to board footprint to suit a soldered connection. If you are trying to mount a specific connector directly on the board then we need more information - specifically a link to the actual hardware you have in mind as there are likely to be a number of variants.