Through consolidating the German government into a dictatorial state, Hitler was able to pronounce himself as the sole leader of Germany, and as such, he could rule all aspects of Germany's social, political, and economic climate. The Nazi Party was able to come into power through capitalizing on the suffering of the German people, who, at the time, were experiencing a severe economic crisis. Hitler blamed Jewish people for this crisis, citing the number of Jewish merchants and Jewish middle-class. Of course, this assertion was ridiculous, but Hitler was an incredibly persuasive speaker, and the desperate conditions in Germany aided his rise to power.
While Hitler's party was popularly elected in 1933, Hitler soon began working to turn the state into an authoritarian government under his control. In 1934, Hitler held a national referendum in which he officially became the sole leader, or Führer, of Germany. While the referendum was a national vote, Hitler had his soldiers physically intimidate and force individuals and organizations to vote in favor of the referendum. Once this consolidation of power into Hitler's hands happened, he was able to fully control German society. Control of the German economy was a part of the power consolidation.
The Nazi regime was, as much as possible, a totalitarian regime. This meant that it did everything that it could to control all parts of German life. Since the economy was a major part of German life, Hitler and the Nazis tried to control it.
There were two main ways in which the Nazis tried to control the economy. First, they tried to control it through coopting it. That is, they tried to get the major players in the economy to identify with Nazism. Fort this reason, they did things like having workers and employers participate in a “Labor Front” which was meant to make them feel that they were a part of the Nazi movement. If groups like the workers felt that they were a part of the Nazi movement, they would be more likely to do what it wanted without having to be coerced.
Of course, coercion was the second major Nazi method of controlling the economy. The Nazis used the threat of violence to ensure that people did what they wanted. They used the SA stormtroopers, for example, to take over the unions and make sure they could not function independently.
In these ways, Hitler and the Nazis sort of used a “carrot and stick” approach. They tried to get the parts of the economy to cooperate voluntarily, but they were also quite willing to use coercion to make sure everyone did as they were told.