Oil drum BBQ

Just an update on BUYING A BBQ COOKER and another humble request for assistance. Darned if I wasn't driving through South Central Los Angeles today coming back from a job, when I spotted a front yard full of beautiful shiny oil drum BBQS! I hung a very illegal U-turn, and 130 bucks later am the owner of a huge cherry red BBQ. It's like a a big shiny red fire truck waiting for me to drive it. When I asked the guy's name he said, "Sweet Daddy" like I was asking who was president. He filled my arms with oak, told me to put a few inches of sand on the bottom, and waved me off. I know this thing will take a special finesse above and beyond my previous experience. There is a second grill up top for slow smoking. Any advice?