If you are using punched strip Board, turn the transformer upside down, solder a spill of .5mm bare copper wire to each pad, push wires through holes and solder underneath to board. Make sure you cut the copper strips between each pair of pins.
Frank
You might have to solder in less than 1 second, otherwise the heat will unsolder the connection on the top side. THinner wire woud slow it down... LED square plated steel leads have a heat velocity of 1mm/sec from tests I did.