Creo Simulate > Creo Simulate > Modeling Structure and Thermal Problems > Structure Loads > Gravity Loads > Preview
  
Preview
When you click Preview, Creo Simulate checks the load for errors.
If there are no errors, Creo Simulate displays the load vectors in magenta. The load vectors are replaced with yellow load distribution arrows when you click OK.
If errors appear, correct the load definition before proceeding.