1. What is your goal?
I know you hear this all of the time.. and it is for good reason. Take it seriously. Like any investment, you need to get clear about what you are trying to accomplish. So you say "I just want to make money!". Well tell me more.
How soon do you want this money to appear? How much do truly expect? What is fair to expect in your time frame? What is this money for? Is the money you earn from this real estate investment going to fund your retirement. Are you trying to make up for that huge loss you took on the last crypto-currency swing?
Get clear about the returns you need, in what time-frame, and how much effort you can put towards the investment.
2. What real estate investment type fits your goal?
There are 334,478 ways to invest real estate (but who is counting?). I like to look at the investment types from a couple of different perspectives. You have investment methods that vary by the amount of time and energy required and then you have innumerous indirect methods like REITs and tax liens.
3. Location, Location, Location...
I debated making this number 1... 2... and 3... So, just understand that no matter how you invest in real estate, the underlying assets are usually affixed to the ground they are built on. Understanding the geography and demographics of your investments can cue you in on any developing or unraveling market trends.
Of course this is not the official complete comprehensive list of considerations for any real estate investment, but I do think it is a few of the most important. Nail these 3 down and you will be well on your way to making sound decisions with your money.