Binders! Cheap ones, Free ones, Donations
Ah, binders. The face-huggers of transition wear. They strangle you, but you just can't seem to take them off. The unfortunate thing about binding is there is not a safe way to do-it-yourself, like with packers or harnesses.
Just going to repeat that, because it's very important: there is no safe do-it-yourself way to bind. There isn't. Don't do it. Jerryrigged options are not options. No ace bandages, no duct tape, none of that. You can seriously fuck yourself up, cause health issues, crack a rib, malform your ribs, and make top surgery (if you're considering it) an impossibility in the future. You might as well have an acid-leaking face-hugger attached to your skull if you bind with ace.
Unless you're one of those lucky motherfuckers who looks flat as fuck with two sports bras on (sports bras that are fitted properly. No size-to-small nonsense. See above paragraph) then you're going to need a proper binder.
Now, there are a few options, depending on your financial situation. You can buy one, snag one for free via a giveaway, or apply to a donation program. I'll cover all three now.
Buying a Binder
There are a lot of binder-buying options out there, and your needs will vary depending on your chest size. One of the older sites out there, and probably one of the first you'd stumble across on your own, is T-Kingdom. T-Kingdom has been around since 1999 and make binders that have zippers/velcro to hold them together. I've never used them, mostly because from what I've heard they're most effective if you're very small-chested. There prices are also probably up there for most people using this blog. So I wouldn't recommend them.
Underworks is another popular option, and their compression shirts are decent. I got my first binder from them - it was gifted to me by a kind guy on reddit - and it helped a lot, even if it didn't match up to my iron-board flat daydreams. It was not very comfortable, though, as the material was rather abrasive, and these shirts are not made specifically for FTM individuals. The pricing is decent, though, so I'd leave it as a second option.
The real frontrunner when it comes to chest binders is currently GC2B. These are chest binders made specifically for FtM/non-binary/etc individuals who have a lot of excess chest tissue but want to achieve a flat chest. They're very reasonably priced (about $35) and come in a variety of colors, full or half-length. I have 2 black full-length binders and they're great. I get the best compression I'm probably ever going to get, the material is very comfortable to wear, and while the full-length will roll up if you don't have them tucked in, it's the happiest I've ever been with a binder.
One head's up: they're currently a very small service and as such, customer service is still basically a fiasco. If you have an issue you're going to want to make sure to keep up contact yourself. But other than that, I've been incredibly happy with the product. They have specific sizing so make sure you measure how they instruct on their Sizing page. You can't just go by your bra measurements.
Binder Giveaways & Swaps
Buying a binder might not be possible for you, whether you're broke or just don't have a source of income at the moment. Luckily, there are a lot of trans guys out there who, for whateve reason, need to unload a binder or two. Tumblr usually has a few giveaways going on (they tend to be raffle-like situations), just browse trans, FTM, binder, & giveaway tags to see if anything comes up. The reddit FTM community is pretty great and sometimes there will be one on there. A really good way to find a binder is to enter one of these communities and just ask. My first binder I got by asking, on reddit FTM, if anyone had one they didn't need anymore - that was back before I had a job & was still living with family (who didn't konw) so it was an excellent, stealth way to get my hands on one.
There are also some trans swap sites, on which users either sell, trade, or giveaway gendered items of clothing - and sometimes things like binders - in exchange for cash, alternate clothing items, or totally for free. The two main ones I've found are
Tumblr Transgender Clothing Exchange - Really active site. All negotiations are with specific people giving things away so I can't account for reliability, but hopefully they're not dicks. Some stuff you can swap for, other stuff is at majorly reduced prices & most people are willing to haggle.
Trans Clothes Swap - another site that does the same thing, though this one seems to have more giveaways than sales (though this may simply be the trend of posts at the moment). Same disclaimer as above - you have to trust the people you're swapping with - but seems like a great site!
If you'd like an option a little more secure than a raffle giveaway or asking, then I've got good news for you: there are a sizeable number of binder donation programs out there.
Binder Donations
Binding is important to a lot of people in the FTM community, luckily, which means a lot of donation services have started up. Some are focused specifically on trans youth, but others you can apply no matter your age. I'll list some of the top ones I've come across (that seem to be functioning/active) here:
FtMEssentials Free Youth Binder Program - This was recently started by one of my favorite trans shopping sites, FtMEssentials, and is for trans youth (aka 24 years of age and under). I definitely recommend applying - or donating to the program if you've got some extra cash for a good cause. Binders received from this program will be, as far as I know, new and un-used.
In a Bind - In a Bind is a binder recylying program, where gently-used binders are given to those who can't afford a new one. This is also for youth, 21 and younger this time around.
5cc Free Binder w/ a Shirt Program - 5cc, a trans clothing site based around raising money for top surgery, has a buy-a-shirt (or other item) get a free binder feature. There is no applicatin process, so they are working on a trust basis that those who use the program really need it. They rely on binder donations, so the wait time to receive your binder might be a while. But - no age requirements! So great for older trans guys who might be in a (wait for it) financial bind.
Replace the Ace - Replace the Ace is focused around ending unsafe binding tactics in the trans community, which is awesome. These binders only ship within the US, and while there isn't a specific age restriction, they do try to focus on younger trans youth (though they are hoping to expand this).
And those are your options! There are a few other binder giveaway programs out there, but some have gone defunct and others I couldn't find a reliable link to. As always, feel free to do your own research.
Before I wrap this up, I'm just going to list a few tips on proper binder care & safely wearing them.
Binder Care
-Wash it about as much as you used to wash your bras. So like...once a year? Ha. But this really isn't a wash-after-each-use piece of clothing, cause you'll wear down it's compression-ness. Once it starts binding less well is usually a good time to do it, since the wash will help it return to its original shape.
-When you do wash, do it on a gentle cycle & cold. No bleach. Ever.
-HANG DRY. Do not put it in the dryer! You'll end up with a binder you couldn't shove a rat through. And it will beat the heck out of it.
Binder Safety
-Do not wear your binder for more than 8 hours
-Don't work out in your binder. Use pec-snugglers (aka a sports bra) Normal everyday activity, or riding your bike somewhere, is fine
-Do not sleep in your binder
-Every few hours, beat your chest & cough hard to break up any phlegm that may have built up
-It's a good idea to give yourself a break-from-binder day every once in a while, like a weekend day when you aren't planning on going out much or something
-It'll probably be uncomfortable to wear, and you might be sore afterwards (especially when you start out) but if you experience sharp pain or trouble breathing take that sucker OFF. You might have the wrong size or binding might not be a safe choice for you
That's it! Enjoy your new-found chest-hugger!