First, make sure you have all of the parts you’ll need to build the kit: the ICSPOV PCB, a DB-9 male connector, and a 6-pin header.
Slip the PCB between the two rows of pins on the back of the DB-9 connector. It can be a tight fit, but if you wiggle the PCB back and forth it should slip into place pretty easily. Align the pins on the DB-9 connector with the pads on the PCB. Note that there are 5 pads on top, and 4 on the bottom.
Solder each of the pins on the top side of the PCB. This works best if you add a small amount of solder, wait a second or two for it to flow around the pin, and add some more to make a strong solder joint.
Flip the PCB over and solder the bottom pins in the same manner.
Now install and solder the 6-pin ICSP header. Be careful not to short the adjacent pins to each other.
One last check for cold solder joints and bridged connections and you’re done! The finished PCB should look something like this: