In the job market, going your own way as a consultant requires you to be able to work fast enough that your customer prefers to purchase your services rather than hire someone who is on the clock. The cold reality of the world is that until you are able to make this economically feasible, you aren't ready to go it on your own.
The guideline is that you have to be able to demonstrate higher productivity by the same proportion as the difference between your hourly equivalent rate and a full-time employee's hourly burdened rate. Otherwise it is cheaper for your prospective customer to just hire someone.
The other side of the coin, contract for events rather than time, ALSo has its pitfalls if you aren't fast enough. You get money only by producing software and selling it. Either you have to work fast to get enough paydays to maintain your existence or you have to somehow find a saleable product so you can make up on volume what you can't make up on speed.
The rule of thumb is that you have to have enough money to live for at least 18 months (and some say 2 years) with limited or no success in order to make a business last. Even then, 80% of all small business fail in that time period.
I don't want to rain on your parade, but I would be doing you a disservice to not lay it out for you to see. It is your decision. You should be fully informed before making it.
Having said all that, good luck.
Now... how do you charge? You have overhead to consider including taxes, some minimal type of insurance, a place to work, and equipment. You therefore have to back-compute things like rent, amortization, insurance, taxes - and the salary you need for the standard of living you can accept (at first) to get started. I recommend that you visit your nearest library for topics on small business startups. They will help you far better than I could, including formulas and points of contact for figuring out taxes, insurance, etc. Also, spend a little money to consult with a lawyer to incorporate yourself in a way that protects your personal things. Otherwise, if you fail you'll lose your shirt. Literally.