For the usual U.S. parallel-parking space on the right side of the road, use your right turn signal. It tells people behind you that you plan to slow, pull toward the curb and occupy the space. If parking is legally allowed on the left side of a one-way street, use the left signal instead. The useful rule is signal toward the side where you intend to park—not toward whichever way you happen to turn the steering wheel next.
Turn the signal on before you slow sharply or stop beside the vehicle ahead. Check your mirror first so you know what is behind you, then signal, reduce speed and move into the setup position. The California Driver’s Handbook tells drivers to signal when they find the space and keep the signal on while pulling alongside. Oregon’s official step-by-step maneuver guide begins a right-side parallel park with a rearview-mirror check and a signal.
Do not change the signal with every steering input
During a right-side parallel park, the steering wheel first turns right, then straightens, then turns left to bring the front of the car into the space. That does not mean the signal should flip right-left-right. The signal communicates the overall parking maneuver to other road users; the steering inputs only change the car’s angle inside that maneuver.
A signal also does not reserve the space or give you the right of way. Before reversing, search all around the vehicle, check the blind spots and wait for pedestrians, cyclists or traffic that would make the movement unsafe. The California safe-driver checklist separately requires signaling, blind-spot observation and yielding during parallel parking.
The exact test expectation can vary
State manuals do not all phrase the instruction identically. California says to keep the signal on during the setup; Georgia’s current driver manual calls for the appropriate signal before beginning the maneuver and again when exiting. Your state’s current manual and examiner instructions control what is scored.
When leaving a right-side parallel space, signal left before moving back into traffic; from a lawful left-side space, signal right. Check mirrors and the blind spot, then yield until the lane is clear.
If the signal direction is now clear but the maneuver is not, use the RouteOS parallel-parking sequence. For a lower-risk setup away from parked cars, follow the cone-practice guide.