Operating in your home state? Form there. Out-of-state formation = double filings.
Online business with no physical state? Wyoming ($100 fee, $60/yr, no state tax) or Delaware (VC standard, $300 franchise tax).
Non-resident founder? Wyoming (cheap, anonymous) or Delaware (if raising US capital).
Nevada and Florida are popular but rarely the right answer.
Next action
Turn the lesson into work.
Pick one concrete next step now, while the context is still fresh.