This is mostly a matter of opinion, as some people prefer EXTREMELY long scarves, and others prefer a short scarf. However, as a general standard, around 4 - 4 1/2 feet is good, depending on the scarf's thickness.
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Absolutely true. If you are making a scarf for charity purposes, they may have specific guidelines. Scarves for military personnel must also follow strict size guidelines.
In general terms, the prevailing theory is as long as the person is tall, but of course, preferences vary. I generally make mine 60" unless the requirement is different.
I knit a scarf for my sister.
It depends on how long the scarf is and how fast the knitter is. Normally a few hours, the number depending on how fast you can knit, for a fast knitter possibly three to four and a half hours solid knitting time.
buy him a scarf. or knit one.
You can knit a simple scarf, or a hot pad.
pencils
One way that one can find information on how to knit a scarf is to take a knitting class. A common and basic knitting starting project is to knit a scarf, so most likely, the teacher would start off with something like that.
As much as its worth depending on the length, color, size and quality
garter stitch is when the rows alternate knit, purl, knit, purl. Since purl is the reverse of knit, for a scarf you just have to set aside a few stitches for your border on either side and knit all of them every row.
Try knitting a simple scarf.
go to About.com and click on hobbies and crafts then on knitting. They usually have at least three scarf projects.
If you are using a bulky or super-bulky yarn, you can knit a scarf thirteen stitches wide. A thirteen-stitch strip in a lighter-weight yarn could be made into a doll scarf, a necklace or decorative narrow scarf, or wrist warmers.
Depending on whether you want the scarf to be reversible or not, you can bind off -- reversible, or knit the two ends together -- not reversible.