Casted on two extra stitches. The first stitch of each row is slipped knitwise. The last stitch of each row is purled. I don’t count these two stitches in following the instructions. I always count garter stitch ridges on the right side.
I used the Chinese Waitress cast on because it looks like same from the front and back. I counted the first row knit as the wrong side. I put removable stitch markers at the center point and to indicate the right side of the work.
I did the buttonholes on a wrong side row. I then added removable stitch markers 22 stitches either side of the center marker to show where the back is for the instructions after the tenth ridge.
Beginning at the fifth ridge, I placed stitch markers just before where the first decrease will occur and just after where the second decrease will occur. On the next wrong side row, I began purling the stitch after the first marker and the stitch before the last marker on every wrong side row. This makes a vertical Stockinette line diagonally along the decreases to match the one I will have between the sleeve increases.
I am still debating whether or not to do the phoney seams.

9/5/2024 I realized that I would run short so I called the shop and got two more skeins of the yellow. I did not get the yarn crawl discount.

After twenty ridges I added extra length at the back to cover the diaper, using short rows. I like the fact that in garter stitch there is no need to hide the wraps. Keep in mind that this was made easier by the fact that I have a marker at the center back and another one 25 stitches to either side of it. I did it as follows:
On the next right side row, (work to 29 stitches past the center marker, wrap and turn) twice. (Work to 24 stitches past the central marker, W & T) twice. Then 19 twice, then 14 twice, then 9 twice, then work to the end of the row.
Work a normal wrong side row.
On the next row, (work to 9 stitches past the center marker, W & T) twice. (Work to 14 stitches past the marker, W & T) twice, then 19 twice, then 24 twice, then 29 twice, then work to the end of the row.