link that explains how that works. Another link here. Since you need over a thousand of them to make a carpet between 90 and 100 cm, I recommend that you either make a felt ball making party offering lots of snacks and wine, or that you calculate several months to make these. I was way too lazy and made only about a 100 before my skin stated to peel off :) from the hot water and rubbing and bought the rest from a local craft woman. It is a pricey project, but it looks and feels fantastic! Wool felt is dirt and water repellent from nature, but I would not place this finished carpet in a high traffic area or in children's room where they can spill sweet drinks or throw up over it.
To make your balls you will need wool fibers which you can get for instance here. I use fine Merino Wool. If your skin is also peeling and you would like to finish your carpet sooner than later, just buy some hand made ones. You just have to make sure that they are all about the same size. I used 2 cm. This shop has nice looking ones 18 pcs for 11 USD. Once you have your beads lined up, you will need a strong tapestry thread and a long, thick needle. Next, you will string the beads in your choice of color sequence onto the string. My daughter was calling them snakes. Once you have those lined up you will roll them and begin to sew them together.
Notice, that I am always sewing the under- row to the top row.
It does not matter what the stitches look like on the underside as they will be covered later. When the desired size is finished, sew or hot glue an anti skid mat.