If you have all the stuff, I'm not sure why there's any question about whether to do it yourself. I, too, am very busy but I always make time to detail my cars myself. I trust (almost) no one else to touch them.
As others have said, Adam's Videos do a great job of demonstrating each step (and associated products) of the detailing process. FWIW, I summarized the steps (and associated products) I use for another black vehicle owner here. Depending on the condition of your Tahoe's paint, you may need to add Step 4.5 to polish with Paint Correcting Polish on an Orange Pad.