There is not any trick or anything you can do. With natural hosts, the clowns should be in quickly. For non natural hosts, it may take a while or never. When there is thread in the tank, like your hand, clowns often seek protection and go into the anemone. Haddoni carpet and LTA have been know to eat clowns that is not used to them so threatening your clowns into your anemone may not be a great idea.