[clovis]

My experience is no matter how detailed the description you give, it will never translate the image in your head to another 100% or even 50%. Don't sweat it.
If your lucky enough to feel inspired, get writing.
I have a story now with five main characters. Two of which are given very detailed physical descriptions because the story requires it. Two are given minor descriptions because there are a few details that are important. One has almost no physical descriptors. I am sure the reader has an equally clear picture in their head of each character regardless. I think you actually engage the reader a bit more if you let them do some of the visual work themselves as a sort of act of self-customization.
If you say someone is beautiful, the reader will picture someone they think of as beautiful. Then if you throw in a specific trait, that may actually clash with what they had in mind. If it's not important to the plot, leave it out.