Silly suggestion, but I'd love it if we had a way to preview what a cloak or set of armor would look like when modified with certain dyes. Even better if you could then pay to 'copy' the preview onto your current armor. As it stands, it's very hard to dye armor without spending half a fortune testing how the dyes look, which portions of the armor are represented by cloth1/2, leather1/2, etc.
Find a tailor station, copy your armour to the model, select the appropriate dye. Names of dyes might not match 100% but you'll get pretty close easy. Might need to cast Light on the model.
When I was playing Laus Hallion I looked over a suit of Enkidu armour in toolset and replicated it very well I think through the station, only 1 of 6 colours was wrong, and only by a shade, oh and I changed the shoes.
Some servers allow crafting or 'previewing' on the characters themselves for modifying armours but they were pretty easily exploitable via logging out during the crafting process, which lead to free armor modifications and duplicating armours, so the tailoring models are the better option offered for what you need, should be able to find them all in the House of Trade.
If you're unsure what colours relate to what parts of the armour (or cloak) and don't have access to these, it might be better to use the Aurora toolset in advance.
That doesn't work with robe models, unfortunately.
There should be a robe model to switch between, one of the robe models is a loincloth I recall copying to the model. Just need to find the option in the list. At work atm so can't go through it with you IG sorry. I think its separate from the torso selections, further down the list of parts to choose from.