Time to goal: How long does it normally take to acquire A: an entry level banking job, then B: A mid-level managerial role?

Based on my experience in investment banking in New York, there is a narrow pathway into this profession, with one exception that may be relevant to you. Typically, investment banks run programs for financial analysts that run two to three years during which time you will be enrolled in brief training and then assume an entry-level job. They usually recruit out of a select number of undergraduate programs that include top liberal arts colleges and schools with strong business programs. People who would like to get into this type of program with a different type of background face significant challenges.

Now for the exception: most major investment banks observe a preference for military veterans. They still maintain a requirement that a candidate hold an undergraduate degree. Have you completed a degree? If you do have a degree, try to look at armed forces alumni networks at major banks. Most of them have some formal way to get in touch with former servicemen and servicewomen who would be happy to serve as a guide to their firms. If you have not completed a degree, you might consider four-year college programs that lead to this path. Unfortunately, free online coursework is not widely accepted as a credential, for now, among Wall Street firms. My comments apply principally to the larger Wall Street firms headquartered in New York, but which maintain regional offices around the country. Another avenue is to find smaller banks that are regional (e.g. SunTrust, Piper Jaffray, Raymond James) that may have different recruiting practices.

Lastly, most entry level jobs in investment banks are meant to be finite -- two to three years, then you are expected to depart. Although there are exceptions to this rule, most junior employees are expected to find another finance job to build their experience or pursue an MBA degree. After a graduate degree, these same people are able to return to the investment banking world on a path to rise in their firms. This is one more avenue for you to consider. If you already hold an undergraduate degree, you can consider graduate business programs. That can be an excellent platform to pursue an investment banking opportunity.

An entry level position gets your foot in the door. This will more than likely be a customer facing. This position will give you experience that you will refer to throughout your career. Your next step will be to become a subject matter expert in that entry level position. This is your opportunity to show managment that you are willing to take on extra tasks and responsibilities.
If possible, find someone in management that would be willing to mentor you. Someone who is willing to answer your questions, guide you and provide you with honest and constructive feedback. Ideally, your mentor would not be your direct supervisor. Your mentor would also give you advice and you should ask them about their career path and how they got to their current position.
Lastly, obtain and highlight skills and knowledge that make you standout from your peers. This is not only from an educational or certification aspect, but something that is specific to the organization. Perhaps the task that everyone else shys away from, if you are the expert with that particular task, then you become a valuable resource to the business and management.

If you want to be in retail/branch banking, then look for an organization that has a manager-in-training program. These programs typically require a BS degree and will work you pretty hard for 2-3 years with the end goal to be a branch manager or in a special services department (loans, mortgage, investments) based on your aptitude. If you have time now, a position as bank teller or in a banking call center would be a good start.

Given your background, business school might be a good way for you to transition into finance. It allows you to gain many of the business and financial skills you'll need to succeed in finance, as well as give you a network to build off of. Additionally, many companies recruit directly from B-school. Your military background gives you an interesting story when applying, and knowing what you want to do after shows you have a goal in mind.

I would recommend checking out Wall Street Oasis (http://wallstreetoasis.com) and checking out some of the conversations about this going on there. The Business School forum will be especially helpful: http://www.wallstreetoasis.com/forum/b-school

I can't speak for banking specifically, but I can say that an entry level job is just that, an entry level job. So, you should be looking for those after school. If you are interested in banking, I would say look for a position there, perhaps a teller, data entry clerk, etc. If not interested in banking, then pursue whatever field interests you the most. If you want to get into sales, then you will want to start looking for internships or entry level sales roles. Just have reasonable expectations, you won't conquer the world in the first year or two, but with the right attitude and determination, you can lock yourself into the right path.

As far as moving into a manager role, completely depends on field and role. If you demonstrate initiative and leadership skills early on, lots of people will look to you for answers helping to secure your place as a leader and look for that promotion. It's important to have discussions with managers as well to ask them about trajectory, the performance review cycle, areas for improvement, etc. It's YOUR career, not theirs, so take charge!