1. Have a 1x1 once a week with each direct for 30 min
2. If you can have your 1x1 walking (go for coffee, head outside) try and do that; conversation flows easier when it's not in a confined space like a meeting room.
3. Loosely allocate the meeting in 1/2: 15 min for them to talk about whatever they want. 15 min for you to talk about what you need to talk about (usually top->down information), and at least leave a few min at the end for career development or tactics.
4. Throw out rule #3 if they want to talk more than 15 min. Always cut your portion down to accommodate them. The point of the meeting is to build trust. Building trust means listening to your directs and getting to know them and what makes them tick. You'll always learn more by listening than instructing.
And that's basically it, that will get you a long way for now!