Before you start, you should know that your involvement at any level can make a great deal of difference in the lives of those in need of mental health care. Often, clients have needs that can't be met by stretched-thin state and local agencies, overwhelmed private and public hospitals and underfunded nonprofits. Because of this, your volunteer efforts can have a direct impact on the life of someone in need of a helping hand.
Once you begin as a volunteer, you should expect to be provided with the appropriate training and resources to perform your assigned tasks. Your work should be supervised, and it should be work that both interests you and suits your skill set. You should receive regular feedback and have access to a supervisor or volunteer coordinator who can assist you with any problems, questions or need for additional training.
Volunteers have expectations and responsibilities of their own. You may be required to work a certain number of hours per week or per month. Once you commit to a certain number of hours, it's important that you fulfill your obligations. In the same way that volunteers' efforts have a meaningful impact on mental health patients, your obligations and responsibilities are real as well. You can't just "blow off" a scheduled shift, thinking it won't be that big a deal because it's "just volunteer work." People are counting on you as a volunteer and expect you to honor your commitments.
You need to learn your job well, understand what is expected of you and ask questions or seek out any additional help you may need. Finally, you'll need to be discreet and respectful when it comes to the environment in which you will work. You may learn very private things about individuals, and you must maintain strict confidentiality so that the trust that others might have spent years developing isn't adversely affected by your actions.