As you see in the pictures, it is always very important to keep same angle of about 10' to 15', which is about two coins height between the blade and the whetstone. Gently push the point you want to sharpen with your first, second and third fingers. While keeping the angle and pushing the point with your fingers, stroke the blade until it reaches the other edge of the whetstone. Then pull the blade back until it reaches the edge of the whetstone. This back and forth is counted as one stroke. Repeat it for about five strokes until you can see or feel some small burrs (edge curvatures). Then move the position of your fingers to where you have not sharpened yet, and repeat this five strokes of sharpening processed from the tip to the base of the blade.
Whichever method you choose, be it a waterstone (also known as a whetstone), or a pull-through (either V-shaped or ceramic wheels) it's important to regularly hone your knife with a honing steel, which we'll also cover below. You'll be pleased to hear that you won't have to reach for the stones too regularly – once every two or three months should suffice. 
You need to adjust your fingers as you move the knife back and forth. Because sharpening takes place under your fingers, start with them at the tip and, as you pull the knife back toward you, release pressure completely and pause. Then, shift your fingers just a little down the blade toward the heel. This finger dance is critical and takes time getting used to.
As you continue to repeat strokes on the first time, eventually a tiny burr will form on the other side of the blade. To check for it, place the blade on your thumb, and pull it backwards. If the burr has formed, it should catch slightly on your thumb (with really fine grit stones, say 2000 or above, you won't feel this). This may take up to 30 or 40 strokes, and is the indication that you should switch and start sharpening the other side.
It is better to understand the difference in sharpening stone materials before you are going to make any decision. Among the available options in the market today, Waterstone, oilstone and diamond stone are the most common type of sharpening stone. Each of stones comes with advantages and disadvantages. Waterstone and oilstone are available in natural and synthetic models. Synthetic are the most common and easy to find as man makes them. As the use of natural stones (e.g. original Arkansas or Japanese natural whetstones) is has diminished in popularity, they are beginning to rare in the market. Artificial stones have a more consistent particle size and controlled with a tight mechanism in providing high-quality sharpening stone.
Understanding Grit: You’ll see a bunch of numbers being thrown around when discussing the grit of a sharpening stone. The number refers to the size of the grit. The larger the number, the finer the grit. A good beginner stone would be a two-sided stone with #400 and #1000 grit. The #400 grit is the courser stone for working out the nicks and imperfections, the #1000 grit is for refining.
A: We’re all told that a sharp knife is safer than a dull knife yet most everyone knows that merely touching a sharp knife can often result in a painful cut while we can wrap our hand around a dull blade with little worry. So why would anyone in their right mind claim that a sharp one is safer than a dull one? To a certain extent it’s a matter of semantics for sure, because there is no denying you have to be extremely careful around really sharp knives. But at the same time there is a very good reason to consider a dull knife to be more of a safety hazard than a sharp knife.
If you don’t have a problem with the water-lubrication system in your working environment, Waterstones is the most common and affordable models to obtain. They are available in various abrasive grit grade from coarse to extra fine mesh. They generally made by Aluminum Oxide, which provides faster cutting. The downside of the Waterstone, they wear down more quickly as the impact of the old abrasive materials that break the stone itself. It is why Waterstone requires frequent flattening to keep it evenly. It is recommended you have one of diamond stones to help you for regular flattening become easier.
Your kitchen knife becomes dull when the metal at the primary edge, the cutting edge becomes fatigued and rolls over to one side or both sides of the blade. This is normal, it should happen regardless of the quality of the steel and what you are using the knife for. The difference will be “when” it gets fatigued, the better the steel the longer the edge will hold out, generally speaking. However, I have noticed something with high quality knives such as a Fujiwara and this may be applicable to you: I have several different brands of knives ranging from mediocre to my one dream knife. Theoretically, the mediocre knives with their mediocre steel should become dull faster under normal use. (I am referring to use at home, not in professional kitchen and not in the hands of someone who cuts lotus blossoms all day long)
Now you may wonder, if a finer stone produces a better cutting edge why do I need a coarse stone at all? The answer is that finer stones work much more slowly than coarse ones. The amount of metal a fine stone removes with each pass is much less than what a coarse stone removes. If you have an edge with a good shape to it from a coarse stone, this is not a problem because the fine stone doesn’t have to remove much metal to improve the edge. If the edge is dull, it will take many times longer to reshape it with a fine stone than it would with a coarse one.
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