Big Walk get shiny is the requirement for the Big Makeover trophy. Unlock the Yellow Tunnel, follow its interior route to the metallic paint area, and have another player apply the shiny finish to your avatar.
Unlock the Yellow Tunnel first
The shiny paint is late-game content and is not part of the first outdoor customization stop. Progress the Yellow Tower route until the group can enter the Yellow Tunnel. Bring an in-game light because the tunnel route includes dark interior sections.
From the tunnel, continue to the dance room and use the back-left corridor. Follow the route until the grey environment changes to red, take the red corridor at the green junction, and continue to the large red staircase.
Use the metallic paint station
The shiny interaction follows the same cooperative rule as the outdoor salon: one player holds the brush and paints another player. A published hands-on report confirms that the regular salon uses a large brush, wall colors, and a friend as the painter.
At the metallic station, stand where the painting player can target the avatar sections and apply the finish. The trophy requirement is short—“Get shiny”—and the Big Makeover trophy should register once the metallic repaint is applied.
If the trophy does not appear
Confirm that the metallic finish was applied to the player pursuing the trophy, not only to the helper. Stay in the same host world until the interaction completes because Big Walk saves progress automatically to the host's game.
Do not substitute an ordinary outdoor color for the late-game metallic paint. The outdoor palette changes appearance, but the documented Big Makeover route specifically uses the metallic paint area beyond the Yellow Tunnel.