Use the KISS (Keep It Simple Stupid) principle, and avoid unnecessary handling of your carry piece (i.e. chambering, clearing, holstering, unholstering)
Decide what condition you want to carry the weapon in and leave it in that condition ALL THE TIME. For me, that's condition 1 with a SAO, in the holster.
If you remove the pistol from your person, remove it while still in the holster and put the holstered pistol in a secure location. I use and highly recommend the push button keyed gun vaults.
IMO, you are much more at risk of having a ND than you are of every having to use a weapon in self defense (assuming you avoid stupid places and people).
Read every ND report you come across and I suspect you will find that most of them are the result of either 1. people "playing" with guns or 2. excessive and unnecessary gun handling.
Good luck and be safe.