I did a little of your pattern stitch to see what it looks like. So I get the pattern. But the instructions are a bit confusing to me.
"From 1st to 4th row sets position of 1st patt. keeping continuity of patt as set work 7 rows increasing 1 st at each end of next and every following 6 rows working inc sts in patten. 35sts. Work 11 row inc 1st at each end of every following 8th row working in stitches in patt. 37 stitches."
Are all the punctuation marks in the correct places, and none left out? Is that an exact quote of the pattern? I'm not sure by the way this is written if the first 4 rows you work are a part of the "work 7 rows", or if you work 4 to start out and then begin another 7. I think the latter is what it is saying, but I'm unsure.
If you work 4 and then work 7 more and the first increase comes "at each end of the next" it would mean to work the 4 pattern rows to set up the sequence then inc at each end of the 5th row, and then again at each end of the 11th row. This is the same way you interpreted it. That would take you to 35 sts.
Then we come to:
Work 11 row inc 1st at each end of every following 8th row working in stitches in patt. 37 stitches."
So you are guessing that means from that point to work 11 more rows and that the 19th row would be an inc. That could be right. Does it make sense with the rest of things?
It sounds like maybe there is more than one pattern stitch you will be doing, working each over a number of rows. Is that right?
As far as continuity of pattern goes. I think it works like this. Your pattern is a multiple of 4+ 3 so here is an example over 11 sts.
____v n n n v n n n v n n n v n n n v row 19, 3rd inc, (r 3 of pat)
keep the 4 rows of pat going until you need the next inc row
______n n n v n n n v n n n v n n n row 11, 2nd inc (row 3 of pat)
row 10 is just like row 6, a row 2 of pattern
row 9 is just like row 5, a row 1 of pattern
________v v v v v v v v v v v v v row 8 (row 4 of pat)
________n n v n n n v n n n v n n row 7 (row 3 of pat)
________v v v v v v v v v v v v v row 6 (row 2 of pat)
________v n n n v n n n v n n n v row 5 1st inc row (row 1 of pat)
__________v v v v v v v v v v v row 4
__________n v n n n v n n n v n row 3
__________v v v v v v v v v v v row 2
__________n n n v n n n v n n n row 1
Start reading this from the bottom and go up like you knit. I showed this more like a chart would be shown, IOW the work shown from the right side. A "v" stands for a knit on the right side of the fabric. A "n" (purl bump) stands for a purl on the right side. So all the even rows as you knit are purled, but I show knits because that is how they will look on the right side. You want to keep all the part in the middle in the same sequence they were in your first 4 rows where you set the pattern up and add the stitches to each end as what they would be if the same pattern was continued.
So row 1 of the pattern is purl 3, k1 so you need to add a knit at each end on row 5. I had to add a line to hold the spacing on the left side, just ignore it and look at the rest. I lined the "v"s and "n"s up as they need to be but the words I put to save myself writing out whole rows may make it a little hard to read. Notice how the "v"s and "n"s line up, ignoring the words as you do so.