1) Choose your job wisely. Either do something fun and exciting, or do something that will give you credible civilian skills, don't just blindly accept whatever openings they have and accept them. Know your interests BEFORE you walk into the recruiters office.
2) Talk to more than one recruiter. Explore all the branches. Find what one is the best fit for YOU. Don't let patriotism or a uniform sway your decision, find what organization has the most to offer you, find what you are interested in. Be leery of pushy recruiters. A 'good' recruiter will give you options and discuss things with you, they may want to get you signed ASAP, but if you ask for more time to make a decision and they rush you, find another recruiter.
3) Basic training is what YOU put into it. Don't be first, don't be last, dont draw attention to yourself. You will have fun, it will be one of the most memorable experiences of your life. Sure, there will be a day that a drill sergeant is going to tear into you, but its nothing personal, its just 'your turn'. Understand that they will challenge you mentally and physically, but NEVER to a point that will harm you. Always remember that. 5 Million people have gone thru it before you, 5 Million will come next, its nothing the average person cant push thru as long as they understand its just an indoctrination. Its just a process to teach you how to follow orders and be resilient.
4) There will be bad days. You will be cold. None of your equipment will work right and you will 100% experience toxic leadership at some point. Learn from all these negatives, learn to appreciate the world outside the military and you won't take as much stuff for granted going forward.
(I was a recruiter for several years. Reach out to me if you have more questions) Good luck!
Honestly, I wish I had the foresight to ask this type of question before joining the Army. It wouldn't have changed my approach but I may have been a bit better prepared. The previous answers all have great points!
Consider both what you want to and don't want to do. When you take your ASVAB, that may help to guide your job selection. Consider studying for this test specifically instead of going in blind. The better you do, the more options you'll have. If you don't want to be enlisted, you'll need a college degree to become an officer. I believe the military can help you with this as well depending on their needs at the time. If you join as enlisted, depending on the branch, you may not have your choice of job. When I joined, the Army was the only one that guaranteed the job training of your choosing. What they didn't say: they can still use you for any other job.
Also, do your own research on what the job entails. "Healthcare Specialist" is a fancy term for Combat Medic.
Here are my big ones though:
Show up at the right time, in the right uniform, at the right place, and most of your day is already set up for success.
Volunteer! If you volunteer for tasks, schools, etc, that keeps you from being assigned the less desirable ones. Plus, the more schools you get under your belt, the more knowledge, expertise, and promotion points you have.
The best days you'll have in the military will be the best days of your life. Unfortunately, the other way is also true: the worst days in the military can be the worst of your life.
I absolutely loved my time in the Army and would 8/10 recommend it for someone else. The military is not for everyone.
Kess recommends the following next steps:
Also, if you are committed to a military career, you can have substantial benefits at the end of 20 years of service....benefits that many civilian in today's economy wish they had, including medical care, pension , etc.
In the meantime, it can be hard work, requiring self-discipline, teamwork, attention to detail, physical demands, etc. but very rewarding depending on the job you chose, so chose carefully.