First, I would find a friend who is already a teacher and visit their classroom to see what it looks like on the job. Is it what you want to do? Do you know what subject you want?
Second, go through the Resources section of MenTeach to see the various options of becoming a teacher. Pick a program that works for you.
Third, decide which subject most interest you AND what is the market like where you live. Are there teacher jobs available in your city? Will you need to move?
Those suggestions should be a good start. It will be challenging although every man who has taught can attest that there are many rewards.
Good luck and we look forward to you joining the profession.