Have reasons for everything that you do and the decisions that you make. Encourage other department employees to participate in the decision-making process and try to establish a collaborative approach by using the skills of each employee. Once you have established yourself as the department manager should an employee try to undermine your success, deal with it directly and forcefully. Suggest the employee transfer to another department or put them on notice that their behavior cannot be tolerated. Give the employee a time frame for improvement and if it is not met, let them know you will be forced to terminate them.
Leadership is a delicate balance between respect, control and motivation.
As you become a leader you will have to become an expert in all these areas. Understand that this is a marathon not a 100-yard dash. It will take time for you to build a rapport with your employees but it can be done regardless of age, gender or any other criteria. Reproduction in whole or in part without permission is prohibited.