If your headset feels loose, too tight or if your vision is blurred or unclear in VR, you'll need to adjust the fit of your headset.
To start, you'll want to gently adjust the lenses by shifting them left, then right until they click into the position that allows you to see what's on the screen most clearly. Next, adjust the side straps. To do this, move the two sliders on either side of the top strap.
To loosen the side straps, move the sliders toward the top strap. To tighten the side straps, move the sliders away from the top strap.
After you move the sliders, center the top strap between the sliders so that the two sides are equal, and the top strap is centered on your head when you put the headset on.
Keep in mind, you'll need to remove the headset from your head to adjust the side straps with the sliders.