Once you've sharpened one side, you need to flip over, but don't swap the hand gripping the blade – think of it a bit like going backhand with a tennis racket (see above). Lead with the heel this time, rather then with the blade, but repeat the process in three parts. After five strokes on each third of the blade, it's time to check your knife. It's not an exact science, and it all depends on how blunt your blade was to start with (mine was very blunt indeed). But if you sharpen fairly regularly, it should just take a few strokes. 
Using the strength of industrial high precision superior mono-crystalline diamonds, Diamond Machining Technology (DMT) have created a durable longer-lasting flat sharpening surface that will efficiently sharpen, hone, deburr and polish almost any type of knife or cutting tool. The DMT set contains 3 one-sided whetstones that have extra-fine, fine, and coarse grits which means you have a complete sharpening system at your fingertips.
When the stone is intended for use on a flat surface, it is called a Bench Stone. On the other hand, small, portable, hand-held stones are referred to as Pocket Stones. Also, because Pocket Stones are smaller than Bench Stones, they are more easily transported but, they also present difficulty in maintaining a consistent angle and even pressure when attempting to sharpen longer blades. Consequently, Bench Stones are commonly used at home or in camp whereas, Pocket Stones are generally reserved for honing an edge in the field.

This is a good size stone and has the two different grits needed for knife sharpening. No instructions were included, but there are many websites with written and video instructions, so this is not an issue for most people. A fair amount of dust is generated during the sharpening process, so protect the work surface and wash the knife after sharpening is completed.
A: Like cars, knife sharpeners run the gamut from basic to luxury and like cars the price can vary from extremely affordable to more than some people might want to spend. You can get a high quality sharpener that will put your knives through a 2 or 3-stage process which will result in an incredibly sharp edge for less than $20. Or you can buy a mechanical sharpener that will produce a virtually flawless edge for $200+.
Feedback is something that is very important to most sharpeners, i.e. how the stone feels when you are using it. Does it feel smooth, creamy and silky or does it feel hard and scratchy. While feedback, pleasant or unpleasant may be a purchase deterring factor it really doesn’t have any effect on level of sharpness that the stone can deliver. Unless of course the feedback is so distracting that it hinders the sharpeners focus and enjoyment and as a result, the sharpener doesn’t like what he/she is doing so that ultimately it does have the potential to negatively impact the results.
You might not need to spend hundreds of pounds to get the best knife sharpener, but you do need to know what you're doing. Warner gave me a crash course in the technique. As a newbie to this method, it took a while to get used to (especially since Warner handed me a knife that had never previously been sharpened) but after half an hour's practice and a little encouragement, I got the hang of it. Here's what I learned...
In addition, the most prized of the natural Japanese Water Stones are quarried in the Narutaki District north of Kyoto, Japan and are commonly available as either bench stones or pocket stones in grits ranging from 120 to 12,000. On the other hand, synthetic water stones are made from Aluminum Oxide and commonly available as either bench stones or pocket stones as well in grits ranging from 220 to 8,000 and, although this is the same abrasive material used to make India Oil Stones, the difference between the two is that the binder that holds the abrasive together enables Water Stones to be much softer than India Oil Stones which, in turn, promotes faster cutting because the worn abrasive material breaks away more quickly and is replaced with fresh, sharp, abrasive material more quickly. In addition, because water stones do not become glazed or loaded with swarf like oil stones can, new abrasive particles are constantly exposed as the stone wears so it continues to cut consistently. Plus, they can be lubricated effectively with water (rather than oil which can ruin some water stones) which combines with the fine particles of abrasive from the surface of the stone to form a slurry which polishes the bevel as the stone cuts. However, it should also be noted that Water Stones do become uneven significantly faster than other types of whetstones although, their softness does make them easier to true again.
High Grit Stones: These are also known as finishing stones with the number range going up to 8000, and give you a super refined edge.  They work great with Western knives as they cutting edge resembles a “U” as opposed to a “V”. If you are using your knife to cut meat, then you can happily stop at 4000 or 6000 grit. If you are only using it for vegetables or fruit go all the way to the 8000.