A drywall finisher's gear list is short, but every piece has to be right. You're kneeling on plywood, sanding overhead, mudding for hours, and breathing whatever's in the air the whole time. The wrong choice in any one piece of gear and you're miserable.
Kneepads first because finishers spend more time on their knees than any other trade. The ToughBuilt GelFit Thigh Support is the popular one — it's a thigh-supported pad so the weight is distributed up your leg, not just on your kneecap. The Klein Tradesman gel pads are the simple version. AltaPRO 50403 are the gold standard for guys who can spend $80. Whatever you buy, buy the gel, not the foam — foam compresses to nothing in three months.
Dust mask: the big debate. For sanding joint compound, a 3M 8210 N95 disposable is the entry. The 3M 9211 cool-flow valve N95 is the upgrade most finishers make once they've had a long ceiling-sanding day. The half-face 3M 7500 with P100 filters is the right answer for an 8-hour all-day sand, especially if you're sanding old joint compound that might have anything in it. Joint compound dust isn't silica but it's not nothing either — guys who sand for 30 years without a mask get diagnosed with stuff.
Better answer is a sander with vacuum attachment — Festool Planex (it's $1500 but the lifetime cost is less than the medical bills) or the Hyde Dust-Free Drywall Sander attached to a shop vac. We don't stock the Festool but we stock the Hyde and the masks.
Pants: white painter pants are common because finishers and painters often work in the same space, but a finisher pant is its own thing. The Carhartt Washed Duck Double-Front in light tan or white is the right call. Reinforced knees because of the kneeling. The Stan Ray painter pants in white are a popular finisher choice too. Avoid dark pants — they show every drip of mud and you'll look like you can't do your job.
Shirts: white or light grey. Long-sleeve henleys for the months it's not 90 degrees. The Hanes Beefy-T in white is what most finishers buy by the four-pack — they're consumables.
Boots: a low-cut work shoe with a smooth sole because high-cut leather collects mud at the ankle and you'll track it. The Wolverine Floorhand 6-inch is the standard. The Skechers Workshire Felton is a sneaker-style work boot a lot of finishers like for the comfort. Avoid heavy lug soles — they'll pick up half-dried compound and you'll be tracking it.
Tools the finisher carries that aren't workwear but are part of the kit: a 12-inch and a 10-inch finishing knife (Marshalltown PermaShape or Level 5), a hawk and trowel for hand mudding, a corner roller, a Columbia or TapeTech bazooka if you're a tape-and-finish guy, and a screwgun (Senco DS235 or DeWalt DCF620). Most finishers I know carry a screwgun even though they're not the rocker because they're going to find a screw the rocker missed and they're going to set it themselves before they tape.
Belt: a finisher doesn't wear a tool belt the way a carpenter does. Most carry a 5-gallon bucket with a tool tote insert or a small Husky apron. The big belts get in the way of kneeling.
Hat: a stretch beanie or a snap-back cap. A hard hat in residential finishing is overkill. On commercial new-build it's mandatory.
Hands: cotton work gloves like the Wells Lamont 1209 for hand-mudding because nitrile sweats and you can't feel the trowel. Disposable nitrile for sanding to keep dust off your skin.
Drywall finishing is the trade where the gear is short but the wrong piece will end your day. Pads, mask, and the right shirt color. Get those right and the rest is detail.