The best way is to work it out for yourself using a multimeter on the ohms setting. If you haven't got a multimeter, I strongly suggest getting one. You don't need to spend much and they are always useful when working on guitars.

With that type of selector switch, you'd solder the pickup output to the tab on the side you want the switch to select that pickup. so if you want the standard arrangement of down for bridge and up for neck, then the bridge pickup is soldered to the lower outer tab and the neck to the upper outer tab.

That type of switch works by actually being two 'normally closed' switches joined together. In the centre position, both contacts are made. In the 'down' position, the lever pushes away the upper metal contact spring from the centre contact block, so that only the lower metal contact spring makes contact. In the 'up' position, the reverse happens.

The enclosed 'box' type of switch (the type normally supplied on PBG kits) works in a different way, and with the switch in the 'down' position, contact is made between the upper terminal and the centre terminal (and vice-versa).