Start by purchasing a good knife. A high quality knife may seem costly, but compare buying a $70 knife you use for 20 years with a $10 knife you replace each year.
Buy a forged, high-carbon, stain-resistant, steel blade knife. It should be rigid and feel heavy, yet balance lightly in your hand. The value of good knives is in the way their stronger metal maintains a sharp edge. Contrary to what you might think, a dull knife can be more dangerous than a sharp one; it may slip when you have to force it to cut.
Sharpen knives with a whetstone (a honing block used with cooking oil or water), a professional-style grinding wheel, or hire a professional service, which may even take house calls.