Well, those sheets I linked above are intended for full PCs - most of the time, it's not necessary to have their background available mid-game, just their rules.
I'd tend to write and print their background separately, but the format people use for that is very much a matter of preference. Personally, I use variations on these categories:
- Name:
- Known Aliases:
- Rank/Affiliation:
- Physical stats
Date of Birth:
Place of Birth:
Species: (if necessary, such as for Xenos, Abhumans or Mutants)
Gender:
Height:
Weight:
Physical appearance:
- History
- Personality/ Beliefs
- Abilities
- Equipment (sometimes includes notes on their attire)
- Known Associates
- Other notes (for things like quirks or minor asides)
- Quotes
For minor NPCs, I'd use a profile like:
They're usually not worth the full profile and rules effort that major NPCs or PCs deserve, so I use
a modified version of the NPC rules from the Architecture of Hate Fanatic Online article. (But their original is a "roll high" D6 based system - like 40k - which seemed to mesh with Inquisitor less well than using a "roll low" D10 system, and gave NPCs very little variety in toughness or weapons, which is why I adapted it).