Pretty straightforward, the flag might bleed into other things, it can be a little gacha, but you know the drill by now. Largest caveat is it really likes blue as it's associated with the colors of the union jack, gets messy if you try other colors. as it doesn't know where to land the blue any longer.

Str 0.8 seems best

invoke with blue dress, short dress, union jack print dress, sequins, sleeveless, collarbone, white knee boots, high heel boots