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By Sandi 05/18/2011
If you crochet them together, even with a slip stitch, it will be ridged on one side. It is however, the strongest way to keep them joined.
And yet, should you ever had to replace a square (ink stain, koolaide, tear, etc), the sewing is much easier to redo and it all lays down flat. If your squares are varigated but with a different color scheme (blue and brown or red and pink) for example, using a color that will blend in with both is best. In other words, don't have a variety of colors and then use white or black to sew them together. It will look lazy and awful. A lot of folk like to border their squares in a solid color, then use that same color to sew them together with.
There are ways to join as you go, and I am including the google search that gives you tutorials that will help.
http://www.google.com/search?hl=en& ... -m1&aql=f&oq=joining+granny+
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