Ask HN: How do I fix my posture after years at the computer?

My posture is absolutely horrible.

I have a pretty bad postural kyphosis (hunched back) that can only get worse if I keep being at the computer the whole day.

I read some stuff about how to fix it (exercising your neck, etc.), but I don't feel like that would solve anything.

I've seen people work standing up, sitting on an exercise ball, resting their feet on a footboard, etc.

How do you guys do it? Is there something relatively easy that I can actually implement and keep doing?