You have to fulfill the residency requirements for state X while also not looking like you live in state Y.

Like another poster said, you can go to South Dakota for literally a day or two and fulfill their residency requirements, but that is not likely to be enough for tax purposes. You should be employed by a company registered in that state; you should have a physical mailing address in that state (e.g. a PMB); you should file a USPS change of address form listing your new mailing address as your official address and change your registered address with service providers like banks and telecom; you should avoid spending more than 182 days per year in any other state as another poster mentioned; etc.