Flyboy.

X Wing Pilot – A pilot, sometimes called a flyboy, directly controlled the operation of a vehicle while located within the same craft. A pilot was often assisted by a copilot, navigator, astromech droid, weapons officer, or other crew members. The term “pilot” was applied across vehicles used on land or in water, air, and/or space. The military designation for a pilot was PL-1. Whether this applied to all pilots or only starfighter pilots is unknown. On smaller ships, the word pilot and captain were interchangeable, but on larger vessels, the pilots were rarely the commanders of the vessels. 

Rebel Legion web site

When I bought my X-Wing Pilot's Helmet at Disneyland, Karli suggested that it would be a great start to a costume, a sentiment that I cautiously agreed with after giving it a bit of thought. However, she immediately raised the ante by commenting that Hallowe'en was only a couple of weeks away, which added a degree of deadline pressure that I hadn't originally had in mind.

But, maybe it's more practical than I think. What's actually involved in creating a Star Wars Rebel pilot costume? How hard can it be?

The basics are easy to find through Google™ as per the reference shot above: an orange flight suit, black boots and gauntlets, the white flak vest, that Darth-Vader style chest box, and those weird belts/straps on the legs* - and the helmet, of course, which I don't have to worry about.

It would cost a bit of money, but most of it would be simple enough: orange coveralls are common, boots are boots, I'd probably make the flak vest out of foam and glue on white nylon material (I can't sew), and strapping material is easy to get at Home Depot. The little chest box would involve some construction, but nothing insurmountable, or I could buy either an Etsy duplicate or a 3D printing template if I decided to invest money rather than time.

But, as always, the devil is in the details, and if you want to pass muster with the Rebellion, there are actually a LOT of details involved in producing a flight-ready uniform that will get you admission to an X-Wing cockpit.

In this case, it's not actually the Rebellion, it's the Rebel Legion, an international organization of Star Wars Rebel, Resistance and Jedi cosplayers (as opposed - literally - to the 501st Legion, which is made up of Imperial, First Order, Sith and bounty hunter cosplayers).  In order to join the Rebel Legion, you need a professional quality film-accurate costume - and they do mean accurate.

The Rebel Legion is very specific regarding the criteria for an acceptable flight suit costume.  VERY specific.  For example, here are the specifications for the white flak vest:

The entire list of requirements can be read here.  Apparently I was wrong, boots are not just boots.

There's some variation from movie to movie: Luke's pilot's uniform from the encounter on Hoth in The Empire Strikes Back is a two-piece combo, and the belts and other accessories are very different from his uniform from A New Hope. In Rogue One, General Antoc Merrick's flight suit is dark blue with ribbed white sleeve appliques, and has a modified flak vest. Regardless, the standards are equally strict.

However, to quote Terry Pratchett, what an insult to the rich and chaotic variety of human experience!**  Surely there must have been some individuality in the Rebel pilot corps - coveralls that were permanently stained by coolant leaks and singed by cockpit fires, someone refusing to give up the battered but functional life support unit that saved their life during the Battle of Yavin, Biggs always forgetting to wear his leg emergency flares, and all the other little real-world quirks that would vary from the strict specifications set out by the Legion.

The final resolution to all of this is that I'm unlikely to pull together an X-Wing pilot's costume for Hallowe'en, regardless of canon accuracy, although the resources to enable such a costume are certainly in existence.  And, ultimately, I'm somewhat inclined to agree with a comment that I read in one of the user's groups that I visited while doing the research for this posting:

"If you show up with the helmet and orange coveralls, you're 70% there."

- Sid

P.S. If anyone reading this is aware of a good source for affordable near-canon orange flight suits, please leave a comment with a link, it would be greatly appreciated.

* These are apparently ejection straps.

** Feat of Clay