Plan an exercise regime, if you don't have one already! Of course every transition is a little different, but from what I've seen weight gain can be common.

It also has another benefit: as you become estrogenized fat gained will be distributed differently, so a good diet and exercise plan can help work off any fat in boy places ready to become the new, beautiful, feminine you! ❤️❤️

Congratulations! That's a big step!

If you're taking oral estradiol, a pill case. Super helpful for figuring out if you remembered your meds. I like the little circle ones with the push button. They're cheap and come with a creating case that's easy to throw in a purse.

If you're anything like I was, you'll have a roughly zero percent chance of forgetting... at first. Once it becomes just a part of your life though, the case helps.

Not directly related to HRT, but get started on that hair removal as soon as you can. I'm still working through my laser treatments and I really wish I'd started them sooner. (A note on that: if you do laser, you'll be told not to shave or use makeup for a week after each treatment. For me, that was a nonstarter. Anecdotal, but this appears to be a liability thing more than anything else as I have consistently done both following treatments with no ill effects).

Sports bras also work very well, especially if you need to boy mode at work or around family.

Find ways that make you feel feminine and confident. Painting your nails, buying new clothes. It helps to have a friend who's also fem around to help you navigate everything, but even if not there's a lot of resources online.

Be patient. Prepare yourself emotionally. Emotional changes were some of the first I experienced. Having good friends and people to talk to can make a big difference.

It's honestly hard to say exactly all the ways you can prepare. Starting on skincare and makeup can be good ideas, but its kinda daunting and not what I'd recommend concerning yourself about first. One of the other commenters mentioned exercise, which is great advice as is eating healthy. A lot of changes are hard to anticipate and how we all handle them can vary quite a bit.

Above all let yourself be excited!! Your wait is almost over :)

If it's something you're interested in, start voice training meow! It can be super overwhelming, so the sooner you start the better. The Seattle Voice Lab channel on YouTube has really good short clips and TransVoiceLessons has really good in depth videos!

I think it's important to note that almost every step in transition takes a lot of time, so you must be patient. Getting on hrt is a big step for sure and congratulations! But be prepared that it will take time to start seeing tangible results from it. Don't be afraid to get started on some of the other aspects like makeup and clothing in the meantime.

That being said, (and this is also partially a personal gripe of mine,) don't be afraid to shop around for a good doctor. Far too many doctors are unwilling to give trans people proper dosages, either out of malice or ignorance, and this can make the process of second puberty much harder of a process than it should be. I hate to reference the infamous Dr. Powers (his personal views are pretty... Weird, to but it lightly. And a lot of doctors practically despise him), but I can't help but admire his patient-first attitude. Even though his personal opinions are kinda gross, he takes his patients seriously and does more in depth testing than any of the doctors I've had throughout my own transition. Too many doctors will give you a bare minimum dose that barely does anything for you and refuse to increase it, citing poorly researched statistics or basing it off of cis hrt which was never designed to induce a second puberty. Listen to your body, keep track of changes and when they happen, and be patient. But don't let a doctor gaslight you into thinking that things are happening when they're not.

And on that note, take some good before pics that you can compare yourself to down the line! It can really help when you're feeling down or feeling like things are too slow, to see how far you've come and what changes have actually happened.

I was feeling pretty frustrated about my transition progress up until earlier this year when I finally switched to injections and was taking a way higher dose. And now I can confidently say that my boobs show through my shirts. As it turns out, I don't think having sub 100 E levels is enough to actually start going through puberty. It did do some changes for sure, but they're basically nothing compared to how my body has changed since I managed to switch.

So I don't know exactly where you are in your journey, but I have some general advice...

If you don't have one yet, think about your transition plan and goals. Obviously HRT is one that falls under medical transition, and there are many others such as hair removal/restoration and various surgeries; and various steps for social and legal transition.

Everyone's plan is different and should be uniquely tailored to yourself. It's never too early to think about.

For example, I wanted to begin with HRT, both to confirm I made the correct decision, and to relieve dysphoria as soon as possible, while giving myself time to work on other things. Now three years in, HRT has done much for me, and I've found confidence to begin tackling the rest, such as electrolysis hair removal, voice therapy, surgical consultations, outfit and style exploration, and opening up to more people about my identity.

It's super cool when you start crossing items off your list and realize all the progress made!

And yes, patience is key. You will most likely have breast tenderness sooner than you think. But that is such an early sign and only the beginning of the beginning of changes to come. Like after two years, I thought my breast growth was finished, but I've recently had growth spurts and rounding, it's amazing. Don't believe everything you hear or read, puberty really is a long slow process.

I would also suggest not obsessively comparing your progress to others. Especially online not everyone is honest about their appearance, and even if they are, there are always outliers who get lucky. Scrolling through selfies of beautiful young trans girls is dangerous, believe ms. I feel so much better and more confident without that in my life. Focusing on myself, building a support network, and making progress at my own pace, those are the keys IMO :)

This isn't necessary but you could get a gaff. I have some from leolines and they are very comfortable and they help alleviate some dysphoria for me. Also I will second the person suggesting exercise. I am doing it myself and it is a very good.