Simple, really.
Go for the hippies, farm-people, criminals, people nobody would listen to.
Stop focusing on america, go for London!
begin taking over orphanages, make disabled people "dissapear".
Infest a child psychologist and talk show host, convince parents to be stricter, and keep shorter leashes on their children.
Infest parents at gyms, coffee mornings, football stadiums, or any sports event.
Fully control all poor people.
Start a revolution, pretending to have the poor people do an uprising.
Have the rich people go to war with the poor people.
While all this insanity is taking up all news TVand talk-show time, infest other countries quickly. Nobody will care about a crackpot tinfoil-hat conspiracy theory, if there's a country at war with itself!
Have all other countries stop the war, imprisoning all non-controllers.