Saving 95% of it. I had fancy, fully subsidized health insurance, then got laid off several years ago and learned about the HSA via MMM. Maxed that out for a few years, then found an employer who offered it with also kicking in $1,500 yearly for the family plan.
Now, I have 30k invested (2k cash) in Vanguard funds. I don't save paper receipts, but scan them and upload them to the provider site. I used a few thousand dollars for moving expenses a few years ago, but outside of that, haven't touched it. I could probably withdraw about 5-6k tax free now, but waiting until I really need to (FIRE or other random expenses, medical or otherwise).