Step 1: Go Get Stuff
(x1) OSRAM-brand photo transistor
(x1) NPN transistor
Step 2: Line Up
Lay the phototransistor atop the NPN transistor such that the base of the NPN transistor aligns with the emitter (longer leg) of the phototransistor and the collector of the NPN transistor aligns with the collector of the phototransistor.
Step 3: Twist
Twist together each lined-up pair of NPN transistor and phototransistor leads.
Step 4: Solder
Solder together the connections of each twisted pair of transistor leads.
Step 5: Trim
Trim the middle pair of wires such that it is shorter, but the connection between the base of the NPN transistor and the emitter of the phototransistor remain soldered together.