Designs for a 3-lead phototransistor?
A two-lead phototransistor is just a three-lead phototransistor without the base lead. When you're beginning, just ignore the base lead (Fig. 24).

Connecting the base to the emitter is sometimes done to speed up the transistor switching off, but as a side effect, it reduces the amplification. If you don't yet know how large a resistor still works in your circuit, begin with something like 1 MΩ, and go down from there.