How do you make money on call options?

You can make money on call options in 2 ways. One way is by buying the option and selling it later at a higher price. Another way is by selling the option, receving a premium fro this, then lwtting the option expire or buy it back at a lower price than you sold it. Both methods require that you educate yourself.

Trading in margin calls is a high risk thing. Educate yourself thoroughly before attemping this. Many people have been financially ruined in a day doing this.