when this object is in roblox studio there is no visible colour contrasts on the creases so how do I create contrasts within blender?
Blender renders the object in a simple manner in Solid View. What you are seeing are shadows not by light sources, but by normals.
Roblox renders lighting much different that Blender’s Solid View. Rendered View may show Roblox-like results too, if you got the dedication to add the sky and other effects Roblox has.
If you want the creases to be visible by the sides in Roblox, you have to adjust your game’s Lighting settings to make shadows more pronounced, but that would affect every shadow, no just creases.
The best method I could only think of Blender-wise is this:
Vertex Paint offers the Dirty Vertex Colors feature. You can adjust the settings depending on how you want the creases to be apparent.
How it would look (quality is low so it loads faster):
This feature lags quite a bit (more apparent on my clinically dead laptop), so consider not dragging the numbers, but manually typing in the values.
The contrasting may still show up negligibly or intensely even if the sides are exposed to a light source, depending on the strength of the contrast.
thanks, this was exactly what I wanted.