Models can make premium accounts like anyone else, as long as they can connect to MFC, either directly or through a foreign proxy, but you should not use the same email address you used when signing up as a model. They will have to pay for their tokens the same way as everyone else, though, and can't recycle the tokens they receive and give them to other models. Otherwise, models could make multiple accounts and bounce tokens back and forth to increase their camscores with no loss of income.