Using a Whetstone:
Whet Stones should be used at least once every 3 months to give you a razor sharp knife. Having a sharp knife is not only easier but also far safer, as you are less likely to slip due to excess pressure.
I would recommend starting with this whetstone Torchtree Whetstone. This kit comes with a bamboo base, 1000/6000 grit stone and a guide to help you get the correct angle.
I would recommend watching a couple of videos before using a whetstone and reading the instructions that come with the Whet Stone.
Top Tips for using a Whetstone:
1. Place the whetstone on a board on top of a towel or cloth to catch any excess water and for safety.
2. Take your time. It will take between 30-40 minutes per knife to get them really sharp.
3. Sharpen your knives every 1 - 3 months.
4. Make sure you soak your stones for 5 minutes, at least, before each use.
Using a Honing Steel:
A honing Steel is used to hone the edge of your knife and not sharpen it. Honing the knife consistently helps keep the edge of your knife in tune for much longer. I would recommend using this on your knife before every use and if chopping a large batch a couple of times through out.
"Unlike sharpening, honing doesn't remove any metal fibres. Instead, the friction caused by running your blade along the surface of a honing steel helps straighten and align metal fibres on the knife's edge that get bent during the cutting process. Without honing, your knife's edge will quickly become dull."
Please see videos below for best ways to use a honing steel.
I would recommend any of the honing rods found here. Honing Rod.