Having major problems decreasing and keeping to pattern

Patter: Row 1 - K all sts Rows 2 and 5: 1 edge st, sl1, kl, psso, 1 yo, cont rep from * to *, 1 edge st. Rows 3, 6 and 12: k all sts while at the same time dropping yo of the previous row. Rows 4 and 7: 1 edge st, out of each st k1 st and k1 st twisted. Rows 8-10: k all sts Row 11: 1 edge st, 1 yo, k1, 2yo cont rep from * to * end with k1, 1 yo, 1 edge st. Rows 13 and 14: k all sts. Cont rep rows 1 - 14.

Now comes the hard part (at least for me)

Left front - shape neck: dec at the left edge 1 st 16 times alt every 4th and 2nd row (1 st 8 times every 4th row and 1 st 10 times every 2nd row.

With the pattern I am making stitches on certain rows which I have had to lose but now I need to decrease so I am not able to make the missing stitches first. I am ending up with hardly any stitches, I do not understand how to keep to the pattern and at the same time be decreasing. I hope that I have explained my problem clearly, if the decreases were on the knit rows it would not be a problem, but they aren’t!! Please help me…I’m going crazy…

Yes, it’s not so straightforward because as you say, some rows decrease across the row (rows 3 and 6) and some increase to bring you back to the starting number of sts (rows 4 and 7). The decreases for the neck are going to be on alternating 4th and 2nd rows, so sometimes they will be on knit rows. For the times that they aren’t, it’s easiest to skip one pattern repeat and just knit the sts, putting in the decrease along the left edge. I would put a movable marker on the needle at 17sts from the left edge (one edge st plus the 16sts you eventually want to decrease) and make sure that those 16sts decrease by one on the alternating 4th and 2nd rows.
So when the dec is on row 2 or 5, skip the first yo. If the dec is on row 4 or 7, skip the twisted knit st and just k1. If the dec is on rows 3 or 6, which are already decrease rows, I would move the decrease to the next row, either 4 or 7 and k1 instead of k1, k1twisted.
You may have to see how this looks in the pattern st as you go along.

I appreciate you taking the time to answer my post. I will put together a plan beforehand following your instructions. It may take me a while to figure it all out but with your help I am determined to master this pattern. Thanks again.