Sure, you know how to paint a wall. But do you know how to paint a wall so that it looks like a wall painted to look like Venetian marble? Well, with some really expensive paint (albeit cheap compared to a slab of Venetian marble) and some step-by-step coaching, you can. At least that's the chipper attitude exuded in the title of Home Depot's how-to painting clinic: You Can Use Faux Paint Techniques. Question is, can you select complementary paints and apply them evenly? Many of the faux painting techniques are self-explanatory — sponging on, ragging off — but applying them with consistency to an entire wall takes patience and endurance. What happens is, your arm gets tired and you start to get sloppy and inconsistent. That's why professional painters can charge $2,500 per room for faux effects. And that's why it's a good idea to test your colors on a small piece of drywall before taping off a room and going for it. Also popular: giving a faux look to a forgotten piece of furniture. Yard sale finds like nightstands and foyer tables can have great second lives. Home Depot's other weekly how-to clinics include You Can Hang a Ceiling Fan, You Can Build a Fence and You Can Build a Retaining Wall With Landscape Block. The clinics are offered much like complimentary snacks at the grocery store intended to persuade you to buy something. In the appropriate department, a Home Depot manager/contractor explains how a project is done, offering tips and answering questions. Shoppers wander up, listen for a while and then wander off. There's no registration and unfortunately also no hands-on instruction. But do you really want to attend a hands-on workshop on building a retaining wall? Do you really need a retaining wall?