Vectorial optical arbitrary waveform generation is experimentally demonstrated by applying polarization line-by-line pulse shaping on a phase-modulated continuous laser frequency comb. Polarization shaped optical waveforms extending a 50-ps time window are successfully synthesized. Temporal Talbot effect is extended into the vectorial regime, where the distinct periodic temporal phases of the two orthogonally polarized pulse trains are exploited. In one example, we generate repetition-rate doubled circularly polarized pulses with alternating pulse-by-pulse handedness. In another example, complex instantaneous field polarizations are synthesized through the combination of line-by-line amplitude and temporal Talbot phase shaping. Our experimental results are measured through a dual-quadrature spectral interferometry system and are found in excellent agreements to the applied shaping controls.