I cast on 45 stitches and worked the 5 rows of button hole band doing it just as it said. This is it explained a little more:
1st Row: P1, *k1, p1, rep from * to end.
2nd Row: K1, p1, *k1, p1, lift over to BO1, k1, p1, k1, p1, k1, p1; rep from * 5 times, k1.
3rd Row: P1, k1, *CO1 (by using a backward loop over the right needle), k1, p1, k1, p1, k1, p1, k1; rep from * 5 times, end CO 1 (as before), k1, p1.
4th Row: (K1, p1) across, end k1.
5th Row: (P1, k1) across, end p1.
Cast off in rib beginning K1, p1, etc.
This works but it makes a very small buttonhole. If you are planning to use buttons that work for that small a hole this will work nicely, and give holes for 6 buttons.
If you need a bigger hole here is one way to do 2 stitch buttonholes across the 45 stitches, but you will only have 5 buttonholes and the spacing will not be 100% even, but I think it will look okay. Do the cast on stitches as backward loops over the right hand needle. (I've heard people say it is nice to have an odd number of buttons for the most pleasing look.)
Row 1: As above.
Row 2: K1, p1, *k1, p1, lift over to BO1, k1, lift over to BO1, p1, k1, p1, k1, p1, k1, p1; rep from * 2 more times, finish k1, p1, lift over to BO1, k1, lift over to BO1, p1, k1, p1, k1, p1, k1, p1, k1, lift over to BO1, p1, lift to BO1, k1.
Row 3: P1, k1, CO2, p1, k1, p1, k1, p1, k1, p1, *CO2, (k1, p1) 4 times; rep from * 2 more times, end CO2, k1,p1.
Row 4: As above.
Row 5: As above.
You may find you want to do a buttonhole stitch (like in sewing) around the buttonholes or to do an overhand or whip stitch around them.