General synonyms:
* Showy
* Gaudy
* Flamboyant
* Brash
* Conspicuous
* Pretentious
* Overblown
* Grandiose
* Boastful
* Loud
* Extravagant
* Effusive
* Demonstrative
* Exhibitionistic
More specific synonyms:
* Pompous: This emphasizes the inflated self-importance of the display.
* Vulgar: This emphasizes the lack of taste or refinement in the display.
* Garish: This emphasizes the harshness or ugliness of the display.
* Tawdry: This emphasizes the cheapness or lack of quality in the display.
* Meretricious: This emphasizes the superficiality or insincerity of the display.
The best synonym to use will depend on the specific context and the desired effect.