You can't make an anemone do anything. After acclimating it to your tank, you can turn your powerheads off to prevent it from getting blown around so it can attach to the rock and find its happy place in your tank.
A sebae can be a difficult anemone to keep and you need to make sure your parameters are stable and pristine, ontop of the strong lighting anemone require since it seems this is your first anemone.