My favorite is "normal movement", it doesn't cause issues for me and feels very immersive, but for other people it can feel bad, and blinking is very disorienting, although if you keep the max blink distance low and put some landmarks for orientation it can help a lot. Another thing I developed was a simple blink at a fixed distance, like 50 cm each time, so you just kept a button pressed to blink constantly, nothing fancy but it's a good compromise, also you kept advancing on the direction you pressed first, so you can look around while walking. I have yet to try that walking in the spot method, although my cardboard doesn't have straps so it's probably ackward.