We are a Sig Sauer house over here
I have a P365X with a red dot and an extended 15 round mag on the cold days when it won't imprint and just standard 12 round mags when I am rockin the t shirt or no shirt. For no shirt I tuck a towel or a shirt in over the gun to cover it nicely. This technique works very well. I've lifted up the shirt up to show people (family friends). They've been floored that there's a gu⁷n under there lol. Works amazingly well and is super easy to access.
One in the chamber, and 2 extra mags always. Then I also carry pepper spray or gel usually in a cargo pocket.
My gf carries too (my P365 with a trigger holster or pepper gel) depending on the situation (fanny pack or Dene Adams corset holster) so I always have backup if needed. We train together and have both quite a few taken defensive classes. My buddy who teaches them was a Navy Seal instructor for 16 years and still travels the country training police and contractors. The guy is something else. My girl may be short, but any man will regret the day they underestimate her. The trigger holster is tied to the inside of the fanny pack
I really like Sigs. If you're a big boi you might be able to fit a P320x in there. For me it just imprints way too much as I'm lean.