I've searched and searched yesterday and this is the Hadith that I came up with.
Volume 7, Book 62, Number 168:
Narrated 'Abdullah:
The Prophet said, "A woman should not look at or touch another woman to describe her to her husband in such a way as if he was actually looking at her."
In regards to what way I want to describe her, well I'll just say that I'll be describing her in such a way that it would be easy to differentiate between 2-3 other characters in the story. (ie, I'm speaking character-wise and maybe some physical features. Like "She was a woman of beauty, her speech eloquent and her gaze could see through to the depths of one's soul." another example would be "Her walk towards the hull of the ship was brisk and such that it demanded attention."
These are just a couple of examples of the many that I'd like to include in what I want to write.
Jazakallah for the replies