Need help understanding a pattern

I am knitting a dress for my daughter that has a wave pattern to it. I have to do some decreases every 10 rows and I am not sure where to do them. I am going to copy the parts of the pattern pertaining to this problem and put it out there to see if there is anyone that can help me.
"Keep pattern repeats centered on garment, working in pattern throughout."
Then under set up pattern, the part for the size I am doing says,
"K1, p1, place marker, work Row 1 of Wave pat to last 2 sts, place marker, end p1, k1."
So, throughout I have been keeping the first two and the last two stitches seperate from the wave pattern.
For the decreases it says,
"Maintaining pat, beg on next row, dec 1 st at each edge [every 10th row]12 times–91 sts."
My question is do I decrease at the very end of the row, eliminating those two stitches on either end or do I decrease at the end of the wave pattern part and keep the first and final two stitches in tact?
I am not very experienced and any help anyone could give me would be greatly appreciated. Thank you.
Smudge

The 2 sts on either end are referred to as selvedge stitches. They often help bring out the pattern, or are used to pick up sts later, or to seam together pieces at the end. You usually leave those alone unless told to do otherwise.

So, I would do the later of your sugeestions…
“decrease at the end of the wave pattern part and keep the first and final two stitches in tact?”

Thank you for your quick reply. I will leave the two stitches alone. That is what I was leaning towards but I just wasn’t sure.

Just when I thought all was good I went back and looked at the pattern again. It DOES say something about the decreases. But I am still a little unsure.

It says, “Work decreases 1 stitch in from each edge. On right-side rows, work ssk at the beginning of row and k2tog at end of row. On wrong side rows, work p2tog at beginning of row and ssp at end of row.”

Now, do I still leave those two stitches at either end of the rows and decrease the wave pattern or do I do it from the edge? I wasn’t sure if this little paragraph that I had missed somehow in the number of times that I read the pattern would change the advice given.

Do the decs in the manner it says - keep one st at the edge and dec next to that.