Reddit mentions of Reebok Men's Performance Boxer Brief Brief

I do want to point out r/onebag (even if you don't do just one bag) has a lot of good information. I've found Eagle Creek compressible packing cubes help keep bulk down on most items, namely clothing. I use a down puffy that packs to nothing and a few underlayers designed for snowboarding for colder weather. Both take up little space and accomplish climate versatility.

Eagle Creek also makes a garment sleeve but I've not used it, instead I just use wrinkle free button ups from Rohan and roll them. One great tip I use is to wear your dressier clothes while flying so you can avoid packing them all together. This takes the complication out of keeping business attire wrinkle free during the flight there and back. Be sure not to overpack things that can be picked up there for cheap, most of these fall into the toiletry department.

(I'm male so this may not be directly actionable for everyone, but materials may be useful*) I have 5 undershirts - the ones in heather gray are a poly blend, two wrinkle free button ups, one pair of outlier slim dungarees, one pair of western rise evolution pant, 7 pairs of synthetic reebok boxer briefs, 3 pairs of darn tough merino racer socks (which get washed by hand), 2x long sleeve base layer for both bottom and top (no link, off brand), down puffy (no link, discontinued), one heather gray uniqlo airism hoodie, and a cheap pair of synthetic shorts for the gym. Most of the stuff gets put into compression cubes or more rarely ranger rolled. It all packs down extremely well.

I also pack a laptop (Asus C302) and some of that dongle life (USB-C). I'm sure I'm missing more than a few things but my goal really isn't to provide a complete packout breakdown, just get some ideas out there for minimal packing/living. It's been a few months since I've packed my belongings into my 30l backpack and took a plane so my memory is a bit hazy but I could do it now if I wanted because I haven't increased/changed my belongings much since.

As a general rule I try to avoid bulky cotton stuff as much as possible and just go with synthetic or merino wool, stuff that will pack down easy. Freezer/gallon ziplock bags can make great compressible organizers if you're looking to save some money. The corners can be reinforced by clear packing tape, with the air pushed out for clothing as well. This is my razor of choice, as it's super light and you can pick up the batteries anywhere in the world.

I wear these at the gym and wear them regularly when it's hot

Bro, I am also a sz 36 waist and I am pretty picky about my underwear. I prefer boxer briefs but every kind I bought either would fall down during the day, or would squeeze too tight in certain areas etc.
 
Finally I found these Reebok spandex boxer briefs in a 3-pack and they are absolutely perfect. I went back and bought 5 more packs of them, and I've been wearing them for like 3 years now. Not a single rip or sign of wear at all.
 
Here they are on Amazon if you want to give them a try. I am genuinely impressed with them and I found that anything cheaper really sucked, so they're worth the money IMO.