If you're on this page, then I have to assume that you're thinking about a full face helmet and you need some information to help you shop for one.
YAY! I’m so happy for you. It can be hard to choose function over form. I get it.
I'm not going to tell you to wear one, but I will tell you how you should wear one and some things to look for. There are plenty of resources on the interwebs which will tell you that wearing a full face helmet will save your brain, period. But how do you pick one?
What Kind of Helmet Should I Get?
The short answer is this: the one that fits you the best. Hopefully this particular helmet will also have the best safety standards, including DOT to ride legally in the United States. But also a snazzy Snell 2015 or ECE. Chances are, the more expensive it is, it will probably fit you better. I know it's not what you want to hear but those brand spend a LOT of time and money to create not only the safest helmets, but the most comfortable ones. The more you ride, the more you will appreciate a premium helmet. However, this doesn’t mean you absolutely have to purchase the most expensive helmet you can afford.
Case in point, the FG-17 to my right. It’s a fantastic helmet for less than $200 with a good intermediate oval fit (somewhat longer front to back and slightly slimmer ear to ear). Typically you need to spend at least $399 to get that combination. And as of the updating of this page (Sept 2018), there is only 1 other option currently available with these features, the Scorpion R710. But the fitment is ideal if you have a rounder shape (shorter front to back and wider ear to ear).
With a helmet that offers higher pricepoints, typically the way that you will directly benefit (aside from extreme crash testing of course) will be in features and comfort like:
cushy liners, typically removable and re-sizeable (ex. Shoei RF1200)
quieter, typically reducing external wind noise (but not silencing all noise)
aerodynamics, typically less resistance when doing head checks at freeway speeds and less buffeting overall at higher speeds
fit, possibly the most comfortable and best fitting for your head shape, e.g. Long Ovals tend to find the Arai Signet-X to be the only helmet that offers a great fit without sizing up to accommodate a longer fit from front to back. If you’re not sure what that means, click here.
How Should It Fit?
Generally speaking, you want a snug fit and buy the size knowing that it will get a little looser and break in over time. Here are a few things to consider when you’re shopping:
Never buy a size that fits perfect the day you try it on in the store, it will always break in so you need to assume that it will loosen up as it breaks in
Never buy a helmet based on colors/graphics/designs; every helmet has a different fit/shape. You *must* find a helmet that fits you well so it can save your brain from serious head injury/trauma, not your self image. But also because the more time you spend in your helmet, the more you will notice any issues with fitment and comfort.
Always buy a new helmet when you buy a used motorcycle. You don't want his/her used helmet, you need one that fits you, not them.
Know your head's measurement in cm/in and general shape
Never buy a helmet that causes pressure points in one region of your head e.g. forehead. If one spot stands out, it will probably get worse over time.
Look at helmets that have some sort of options when it comes to resizing/adjusting fit, like Shoei or Arai. These brands allow you to order different cheekpads and headliners in millimeters to you can fix things later if you made sizing or fit mistakes early on.
make sure you have Zero pressure points (like your forehead hurts or the back of your head feels squeezed)
it should all feel equally uncomfortable until you break it in
snug, enough so when the helmet is on (unstrapped) a person can't move the helmet up and down
only enough room in front of your forehead to fit your fingertip (not the whole finger!)
cheekpads can be changed, most of the time! dont fit your helmet solely by the cheeks
when you put the helmet on the first time, it can be weird. try putting it on again a few min later to see if any pain or pressure you felt before goes away (I find most ppl new to helmets have this happen a lot)
when you think you want to buy a helmet, make sure you wear it around the house (without throwing away any tags or boxes) for at least an hour to give you an idea of how it's going to break in and feel when you go riding