Why waste hours together to make a sketch manually? You can easily generator sketch of any image in less than a minute with the help of Sketch Generator, an online free sketch making tool.
It is an image processing utility that can generate a “sketch” like abstraction of your digital photograph. Simply upload the picture, configure sketch settings and click on ‘Generate sketch’ button. There are three configuration options:
1. Sketch Resolution - Higher resolution results in finer, more responsive sketch lines.
2. Sensitivity Threshold - This sets the level of detail that will be sketched. The lower the number, the more dense and detailed the sketch.
3. Colors - These are the RGB values of the sketch’s foreground and background colors. Each entry’s value may range from 0 to 255.
Here is a beautiful sketch of my favorite Aishwarya Rai:

Please note, output of sketch will vary a lot with the change in sketch settings. To get a finer sketch, set Sketch Resolution to ‘high’ and Sensitivity Threshold more than 50. For colored sketch use RBG settings under colors option.
Sketch Generator: Click here to create a sketch
Found this on Technospot and in case you want to sketch manually in a group then check out SwarmSketch. There are more tools to play with your images here. Get set and have fun with your images!
cool aish looks nice with that effect
Very cool tool, thanks for sharing!
i already know this sketch generator for years.