STEP 1:PLZ DOWNLOAD THE IMAGEs FIRST FROM HERE[
http://www.hjsstudio.com/twistangle.html]....IT WILL BE HELPFULL TO UNDERSTAND THE TUTORIAL
STEP2: MAKE A TWIST MEASURING CARD
First you need to make a card marked with angles to measure your yarn against. Find a protractor or other device marked with angles, and a lined 3 x 5 inch index card. Cheap plastic protractors are found in the stationary/school supply section of most stores.
You can see on the card pictured here that the "0" degree line is straight up and down along one of the lines on the card. Mark the halfway point on that line. All your angles will be drawn from that spot.
Lay your protractor so the hole is over the center mark, and the "0" degree line is right on the line on your card. Use a pencil to make a short line at the 5 degree, 10, 15, 20, 25, and 30 angles along the edge of the protractor. More can be marked if desired, but I wouldn't bother unless you routinely spin very high twist yarns. If your card is too short for the size of the protractor, place the card on a piece of paper and, making sure the card doesn't move, mark the angles on the paper.
Finally, carefully draw straight lines from the center mark to the pencilled marks for each angle, and write in next to the line which angle is which. Repeat on the other end of the card so that you'll be able to easily measure twist angles for both 'Z' and 'S' twist.STEP3:MEASURING TWIST ANGLE
Picture illustrates measuring the twist angle of a singles yarn. I've anchored the yarn in a small slit at the top of the card, and I hold it straight, parallel to the lines on the card, with my finger. Don't pull it tight--just hold it under enough tension to keep the yarn reasonably straight. More tension than that will stretch the yarn, making the angles measure more shallow than they really are.
If the yarn is quite fine, or all one color, it helps to have a magnifying device of some sort handy. You can see a device to the right of the card, variously called a pick glass, linen tester, or map reader. It provides 10 times magnification. I can easily pick it up and place it on the yarn to see it more accurately.
To determine the approximate twist angle of this piece of yarn, look at the slant of the individual fibers--readily visible in this section. Whatever angled line on the card most closely matches the slant of the fibers in the yarn is that yarn's twist angle.
More than likely, different sections of yarn will have slightly different twist angles. The more smoothly spun the yarn, the more accurate this method of measuring twist will be. That's one reason why I only mark every 5 degrees on my card--not being a machine, my yarn will never be perfectly even. More accurate measurements would be possible, but not really tell me anything important about my yarn.
If you keep the card (and magnifying glass) next to your wheel, you can stop spinning at any moment and easily check the twist angle of your yarn. Then you can adjust your spinning as much or as little as needed to keep the yarn spun like you want it. For low-twist yarns you may need a twist angle of around 10 degrees. For yarns to be plied into socks, you might need a twist angle of 20 degrees. Whatever you decide is good for your project, the card will help you keep on track.
FOR YOUR KIND INFORMATION: THIS IS NOT MY RESEARCH, ITS A COPY PAST WORK BUT I GUESS, EASY WAY OF THINKING ENGINEERING .....