The "evenly" refers to the picking up rather than for just the knitting. That is, you have the section of double moss stitch, and you want to pick up 6 stitches distributed evenly across that section. (so if there are, say, 24 stitches in the double moss area, you'd pick one up every four stitches) You then pick up 37 stitches along the edge -- I can't see the pattern because I don't want to buy it
but it looks like you have an edge that's part double-moss-stitch and part normal knitting? If so, you pick up 6 stitches from the double-moss-stitch section and then 37 stitches in the rest of it, all distributed evenly -- the 43 total stitches comes from 37+6.
...And the pick-up-and-knit bit counts as the first row, so then when you go back across you start with the second row of the moss stitch pattern. (Pretending, as it were, that you've already done the first row in moss stitch, even though you didn't.)