And you shall make loops of blue uses the singular you. The word for blue is the same as in verse 1. (But see the discussion on this color at 25.4.) The material from which the loops are to be made is not specified, but the word for blue at times means “blue wool” (New Jewish Publication Society’s Tanakh). New American Bible has “yarn.” To be safe, Good News Translation and Contemporary English Version have “blue cloth,” and Translator’s Old Testament has “blue material.” The word for loops suggests a “U-shaped” doubling of the blue yarn with both ends of the “U” sewn to the edge of the linen curtain, leaving an opening just large enough for the gold clasps (verse 6) to pass through. In some languages it will be necessary to make the action of “sewing” explicit and say, for example, “Make loops out of blue cloth and sew them to the outside piece in each set,” or “Use blue cloth and make loops….” In some languages “loops” will be rendered as the equivalent of “ears” or some similar object.

On the edge of the outmost curtain in the first set means that these loops were sewn along the 28-cubit length of one of the two pieces made according to verse 3. The word for set is derived from the word meaning “to be coupled” (“joined”) in verse 3. It means “what has been joined.”

And likewise … repeats the same instructions for the other piece. Good News Translation says it all in fewer words: “Make loops of blue cloth on the edge of the outside piece in each set.” This was to prepare the two large pieces of linen cloth to be joined together along their looped edges. Each set was twenty by twenty-eight cubits, and they were to be joined to make one large piece twenty-eight by forty cubits.

Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .