Solution 1: First try a rebake (CTRL+ALT+R) several times. If that does not help, select Rebake from Advanced>>Character> Rebake Textures.
Solution 2: Check your inventory > Worn Tab to insure your are wearing your usual shape, clothing, etc.
Solution 3: Try wearing different Shape/Skin/Hair/Eyes
HyperGrid Users: It is very important that you make sure your avatar has fully loaded on your home grid before making the hypergrid jump! If you do not wait for your avatar to fully load on your home grid, you may appear as a persistent cloud when you jump to the Neverworld Grid.