Great question. I am an adolescent therapist (ages 11-20) for clients with behavioral and/or academic issues in school. Many of my clients have learning disabilities as well as mental health concerns. My process is different than most. I begin with a referral from a school district. I speak with teachers and administrators and special education. From there I interview parents and siblings. When I see the adolescent I perform some psychometric tests. I work with all of these people throughout the process to provide an atmosphere and conditions where my client can become more successful both in and out of school. Occasionally I even include the juvenile justice system when warranted. My point is that while there are certainly basics where therapy is concerned, the process can be very different depending on the client's circumstances. I hope you find my answer helpful and informative.
Do you have a friend you talk to a lot about important and personal things? Do you trust her opinion and feedback when she shares it? Therapy is a like that...with additional components. Therapists are trained to listen well and attempt to build a relationship quickly, as they don't have as much time as say you and your 'close friend'... (called an alliance). They are also trained to keep professional boundaries, so it stays a therapeutic relationship (More one-way) rather than as "good friends" (More of a both-ways relationship). There are different types of therapy they could be trained in and help with the process, and different tools can be used to help identify the issue to address. Much like other careers, many therapists will specialize in a certain area. Depending on the patient/client/person they may have significant awareness and understanding of their concerns or problem; or they may not. The therapist's job is to help them identify and understand the issue and how they want to proceed to manage it.
So it's mainly an exploration (where are we, what's really goin on) and a journey (where do you want to go, how do you want to handle it) to go from one place to another. Great question.