This is very simple. You combine four colors but same yarn quality.
You begin with magic loop.
You begin to crochet in the magic loop three half double crochet stitches with each color.
(Figure 1) You have 12 half double crochet in the magic loop.
Let's say you begin with red color.
You crochet three double crochet with red.
Change with the yellow yarn and crochet another three double crochet.
Change with the purple yarn and crochet another three double crochet.
Change with the green yarn and crochet another three double crochet.
(Figure 2) You continue to work over the previous three half double crochet of each color, changing each tine the color.
You continue to work over the three double crochet of yellow yarn with the red one and then change the color to yellow.
You continue to work over the three double crochet of purple yard with the yellow one and then change the color to green.
You continue to work over the three double crochet of red yard with the green one and then change again to red.
(Figure 3) Don't forget to increase each time it is needed with two half double crochet in the previous stitch, in order to have a real rug.
(Figure 4) You can use this pattern to make pillows, rugs, granny squares, hats, and whatever accessory you like.
Good Luck!
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