Hi Judith,
Welcome to the forum. I'm Adrienne, the Deputy Editor at LK.
So, you've got your 19 sts (I take it you're working the third size?), where it says 'Next row: work in patt' this refers to the lace pattern without decreasing so you should work this in just stocking stitch. You will still have 19 sts at the start of SHAPE SHOULDER. Again, work in stocking stitch without decreasing but only work 13 stitches on that row. Then wrap & turn - see the special abbreviations on page 36. Leave the end sts unworked.
This is why you only have 13 sts. You're not actually decreasing them, you are just stopping the row before the end, turning, then working back along the WS for the Next row.
Hope this clarifies things, let me know if you have any other questions.
Adrienne
