Getting close to 6 months here now, started in late June.
My "little guy" is much bigger, you'll notice that right away and it just keeps on growing, we're talking like an inch here, wow.
I've gained weight, while not gaining any more body fat, that may actually be down.
I outgrew my "girl pants" my waist got bigger by a couple of inches. Had to get men's pants and a new belt.
My jaw's squarer, nose a bit bigger, brow ridge a bit more prominent, and interestingly, as my face becomes more male, I can see an indentation, like from a very old injury, on my forehead. Triangle-shaped. It doesn't match any of the whacks I remember, so it must be from young childhood, I was a crash-and-burn kind of kid.
Most of my t-shirts are "muscle shirts" now and the extra shoulder mass takes 'em up and makes most of them too short to tuck in and stay in.
Your smell will change. How do I describe this delicately? Exit fish, enter cheese.
I've been getting bigger shoes, and they fit me fine. I'm overjoyed to find a pair of England-made Docs, used but you can't wear these things out, European size 40 and I've been size 37 for years. They're a tiny bit big but fine.
Your voice will change, mine felt "boomy" for a long time but my guy friends kept saying "No, it's the same" but friends I haven't seen for a while really notice the difference. I'm getting some squeaks too, very annoying. My voice is like a teenage guy's right now.
You'll get more hair, and in more places. I'm just starting to get a "happy trail" now, my head hair is coarser, facial hair coming along slowly, most people get more hair coming along than I have, some FTMs are quite hairy.
You'll get more horny, even if you're already a pretty horny person, you'll get more horny. You'll gain a new appreciation of porn lol. No need to jump into the deep end here though, just a good make-out scene is as hot as anything.
If you're under 25 you may just grow height-wise. I know I put on another inch or so in the Army, that good Army food (don't laugh it WAS) at age 20 or so, T may help you grow more than otherwise if you're lucky enough to start this young.
I notice my endurance is up even though I haven't been training for endurance at all. That's cool. Strength is up too, I notice from lifting things like electric car batteries, bags of feed, big ol' disgusting bags of trash, etc lately.
In the excellent book The Testosterone Files, the author mentions the big changes being in the first 2 years but changes still showing up for many years.