Forget using a knife to peel the skin off that knob of ginger or turmeric - use the edge of a spoon instead.
That way, you don't waste any part of the flesh.
Turmeric tends to stain everything, including your fingertips and fingernails, as well as porous kitchen counter surfaces, so be careful when handling it.
One no-brainer way to keep the root from staining your hands is to wear a pair of disposable gloves. When we're in a rush, we're more likely to skip this step but try to remember to put on those gloves - it'll save you from unsightly yellowish stains that can last days after peeling the orange stem.