1) Save back a year's worth of living expenses and set that aside in another back account. Knowing that you have that money saved in case something goes wrong in your attempt at a poker career will save some stress and headaches.
2) Proper Bankroll Management. Research how much you will need to make a month to live how you want to live and make sure you are rolled for it.
3) Money Management. This kind of goes along with your bankroll management, but remember to see your bankroll as a high-risk, high-reward investment. I used a 1/3 rule back when I actually had a bankroll attempting at a part-time income. 1/3 of profits go to me. 1/3 of profits go back into the bankroll. And 1/3 of the profits are set aside for taxes. Of course, depending on where you live, taxes may vary. Just know your local laws on poker taxes.
4) Determine location on where you are playing. If you are playing online, make sure they have the tools, resources, and player base you need to be successful. If you are playing live, I recommend living in a place that has at least 2 or 3 different options. If you live in a city where there is just 1 poker room and usually just runs 1 or 2 tables a day and with the same players every day, it's going to be difficult to make a living with that kind of player base.
5) Make sure you put in the time to study.
6) Track your winnings & losses. Record everything. Track your
hands if you can, so you can go back to #4 and study.
7) Stay consistent. If you really want this to be your job, you're going to have to be consistent. And it's easy to get burnt out.
8) Work your way into it. Start out part-time using proper bankroll management and don't quit your day job just yet. Give it a few months and see if you can and are willing to put in 10-20 hours a week playing and building a bankroll. Use that to "test the waters."
I'm sure there are other rules you should stick to, but that's a start. Good luck if you decide to give it a grind.