My response when I was online dating - “I’m in car sales, so expect terrible aftershave, cheap suits and awful patter. Fancy a drink for you to experience this in the real world?”
I work with computers. I said "I work with computers because they don't talk back and I don't like people"
Note the self depreciating joke here used by the successful online daters?
Both replies show humility and an ability to laugh at oneself, they have wit, they are not trying to impress.
In fact they're actively going out of their way to make themselves sound bad, but it works? It's nice isn't it it made you smile and feel a connection for them?
Not because of pity or woe is me but because it shows they're comfortable enough with themselves that they can be the butt of the joke, which means they actually must be really quite above what they say.
And it's very easy to think of something to reply to.
"I sell cars"
"I work in computers"
Is very hard to reply to, but their little jokes there's loads of flirtatious banter I can say back off the tip of my tongue which means that reply is much more likely to happen.
You've got to make it easy