I think this is a link to the pattern and chart
Remember, the individual blocks don't represent stitches. Sometimes they stand for increases or decreases or for no stitch at all, for example. The first row of the chart uses 25 sts and does not include the 3 edge sts on each side. The 31 cast on sts includes those border sts. The chart may be a little hard to read since there's not a big difference between the | for a knit and the \ or / for a decrease. You might go through and highlight some of these to make reading the chart easier.
Begin the first row with knit 3 and then start the chart (at row 2) with k2, yo, k2tog, yo, k2tog etc and see how it goes. The yo doesn't use a stitch, just bring the yarn to the front and over the right needle.