How did spain control the economic activities of its colonies?

Spain would give any of the land that Spanish explorers landed on to the Spaniards to farm or cultivate anyway they saw fit to turn a profit and to convert the Native population as they saw fit to Catholicism. This, of course, did not take into account it wasn't their land to give away and the Native Indians were not theirs to control. Once this began it was more like another slavery situation. Then the Spaniards mined the minerals, especially silver and gold, from the land and sent it back to Spain. When these began to run out, the slavery institution had been instilled so large plantations produced sugar and they also sold the natives as slaves. Eventually, the mines began to run out and the Spanish could not longer pay for the necessities with gold from Spain. In order to keep the colonies from becoming self-sufficient they forbid them to make paper which was needed for government bills and legislation.