I'm not great at capturing real people. This is a sketch of the character Woolsey from Stargate. I think it's *almost* there but I don't think his likeness is immediate.
One method an artist can use is to trace from a photo. "Trace" is one of those words that is quite loaded because a lot of us grew up hearing "He traced it" as a slur against your skills. To be clear: tracing is not a bad thing. It's a useful tool. Artists trace their own work all the time.
And it's even fine to use a photo reference under your drawing surface as a guide. Of course you don't want to literally copy it because a) boring and b) copyright. But using it as a guide is helpful.
In this case I wanted to avoid that and just draw from reference by "eyeballing it" as they say.
This is not a skill I've put to the test very often. I'm a cartoonist focused on fantastic subjects like spaceships and barbarians. But I did cut my teeth in life drawing classes all these many years ago and that foundation has been priceless for me.