Hi Samantha
You are most welcome.
Your choice of clothing is a very personal one and wearing what you want, will not change who you really are. However long ago in the dark ages. I contemplated the same thoughts you are having now. Do I go dressed or just some plain clothes? I remember reading something about dressing up and going to see a psychiatrist and the expectations that the pyschiatrist would have, that is, if you were not dressed, then you were not serious, so to speak.
When my time came for my first visit. I was casually dressed, skirt, blouse, a little makeup and my hair in a plait. The main reason I chose this way was, one, I was able to present as a female with no problems and two, to make sure that the psychiatrist realise that I was deadly serious and I was not playing games. My second visit I was dressed in a semi formal suit because that was the way I went to work and that was how I wanted to present myself at the time. After that I do not really remember how I was dressed, except to say, I just went in as me, regardless of what I wore.
So how you present is going to depend on how you go about your change and how well you can present now. It's hard to speculate on what will happen in the future when you mention that you are pre everything in a sense. I would not say anything to HR about what you intend to do at this stage as you have only just started out and as you have mentioned this job will be gone by the end of the year, you can reassess about discussing this issue with HR if circumstances change in the future.
What are you plans at the moment? Can you present as female now and what have you done to help you achieve what you want in life? These are just some questions that will help you decide how you go about achieving what you want. Ultimately it is up to you how you go about achieving things, we can give you advice and opinions, but you have to make the final decision on what you want.
However most important thing you can do at the moment is to, 'do the things that will make you happy' and know that there are a lot of people around here who will help and support you.
Warm regards
Sarah B