Guild Wars 2

I was recently delighted to find that a friend had gifted me an armor skin I desired from the gem store, but before I make use of it I had a question.

I understand that using said skin will consume the item to apply to w/e piece(s) of armor I choose, but is the skin then added to your account wardrobe the way any other skin is? That is to say, from then after am I able to simply use transmutation charges to continue using said skin on armor in the future?

Yes. The first use is free. After that, it goes into your wardrobe and requires a transmutation charge from them on.

It will be added to your wardrobe once the initial item is consumed and will, after the freebie, require a transmutation charge. That is correct.