The magic loop knitting method allows you to knit projects in the round even if you don’t have exactly the right length of cable needle and/or don’t want to use double pointed needles. The traditional magic loop method uses one very long circular needle. An alternative magic loop method uses two sets of circular needles. I prefer that one on larger projects like sweaters and this traditional method on smaller projects like hats.
Magic loop is particularly helpful if the size of the project (number of stitches that make up the round) changes as it goes along, like with a hat that gets narrower near the top. Using traditional magic loop allows you to own the fewest sets of needles, because you can substitute circular needles for straight needles, and the traditional magic loop means you don’t need multiple sets of circular needles or double pointed needles; with one set of interchangeable circular needles, you can knit pretty much anything.
The following video shows you how to knit with traditional magic loop:
Cushion of Joy 