Her costume and make-up are very different through the world.
 
She's usually wearing black and white leg warmers.
In London and similar productions she is/was wearing long gloves, while in other productions she's wearing black and white hand warmers.
 
Her color is white/black/"purple" in most productions. However in Hamburg, Stuttgart, final Broadway, and some other minor productions (like France, Sweden, Norway) she is more brown/white/black. The only part remaining in all productions is the white spot on her left hip.
 
Her make-up and wig have the colors of her unitard.
 
In Japan, Sillabub is bright yellow, while Jemima has black,white, and red/orange colors with a make-up looking more like usual Jemimas.
In the recent productions in East Europe or US Regionals, she's harder to to recognize as costumes are completely different from what we are used to and from a production to another one.