I'm gong to Canberra (Australian capital city) to represent my university at the end of the month where I will be sharing a hotel room for 4 nights with 1-2 cis guys that don't know me and dont know that I'm trans.
As you guys know I'm pre-op, so I'm a bit nervous about the situation. Any advice?

when you take your binder off to sleep maybe you could put on something tight but not as constricting as a binder and then like a robe on top? i mean its odd but "why is that guy wearing a robe" is better than "why does that guy have boobs"

If I were you; No matter what style of clothing I usually wear, I'd bring clothes that are a bit bigger than what I usually wear,
Layering also helps.
I don't know what your T schedule is, but if you have to take a shot, obviously, don't forget to hide that, and I'd take my shot before they all wake up so that they don't question anything if you step out with a bag of stuff - and don't put a needle wrapper in the garbage.

I'm actually not sure what kind of advice you're looking for...
What are you most worried about?

During my freshman year of college I shared a suite with one cis guy though he knew I was trans and was extremely supportive.  After showering I would grab my towels and clothes and hug them over my chest so that it just looks like I am carrying clothes, maybe carrying a blanket or something could help while you are going to and from the bed or bathroom. You could layer shirts or buy a binder that is too large  to wear to bed so that there is some binding but not nearly as tight. Sometimes during the evening when I wasn't binding I would wear a hoodie that is a bit bit and just cross my arms when I left my room to use the bathroom or to get food.

Try not to over think it. I went on a trip with my high school once and I stressed out to where I was having panic attacks during the trip.  It helped calm me when I would tell myself that I was just a normal guy with nothing to hid because I was over thinking every scenario possible.

You could always make sure you "put the seat back up"

TAKE LOTS OF CLOTHES!!.

not for any other reason than Canberra gets bloody cold.

Thanks for the responses 

I'm on 3 monthly injections so I don't need to stress about that - my Dr always does them.

I can't layer up too much or wear hoodies as I'm going to be in a suit or dress shirt most of the time that I'm there. It's a forum with local and federal MP's so we need to be really well presented. Should I wear a plain t-shirt under the button up shirt? I'm worried my chest will be more obvious :/

Bradán - Thanks, I will take a couple of loose-ish binders that I can take to use while I sleep. 

GentlemanRDP - I guess I'm just a bit stressed and looking for any little things that people can think of that I might need to consider so that I don't out myself. I'm stealth at uni. I don't know what I'm most stressed about, being walked in on in the shower maybe? haha

Nicole - Isn't Canberra having sunny weather still? Victoria sure is.

If you are worried about getting walked in on in the shower, just make sure your not facing the door, face the wall or something so they would only see your back. Hopefully there will be a lock and the other guys will notice the sound of the water anyway