Plug your instrument into the input jack (this switches the battery on) and plug your amp into the output jack.  Flip the COLOR switch down and adjust the RATE control to a middle position.  Strum and open chord.  If no effect can be heard, step on the footswitch.  The footswitch bypasses the signal directly from the instrument to the amp.

The RATE control adjusts the speed of the phasing sweep (clockwise rotation for a faster rate).

Now snap the COLOR switch up.  Notice how this carves into the frequency spectrum hollowing out the sound.  Fundamentals and harmonics glide in and out for an extremely pronounced shifting effect.  Return the COLOR switch to the down position and notice the fullness again.  In the non-color position, with the sweep speed at minimum, the effect is not as strong and if the slowest sweep is desired the COLOR switch should be in the up position.
-AC OPERATION-
Notice that the Small Stone Phase Shifter has been provided with a small jack between the instrument and amp jacks.  This allows a battery eliminator to be plugged in so that the battery can be saved.  The Electro-Harmonix tip-positive 9 volt 100mA adapter is recommended.

Do not run the unit from an eliminator without an instrument plugged in as this may result in feedback noise.  When switching from AC to battery operation, pull out the AC power wire, pull out the instrument cord, then re-insert the instrument cord.  The unit is now functioning on battery.