It's not only the experience gained while completing an internship that is valuable, it's also the first-hand exposure that helps decide if a future job in a particular field would ultimately be enjoyable and worthwhile; consequently, the value of internships cannot be understated.
What makes for a valuable internship? Although it's a hard question to answer, understanding yourself and knowing what you're looking for will provide a framework in understanding what type of work you are ultimately looking for. It's important not to take this question too lightly for it is this self-assessment phase that yields the most important answers.
Once you have evaluated yourself, it's time to do some career exploration followed by actively engaging in the networking process and searching for internships.