First Ever Pattern - confused, please help

I’m following a pattern for a sweater and am working on the sleeve. It says:
Work 32 rows stocking st, inc one st at each end of 3rd row, then in every foll 10th row 2 times.

I take this to mean:

Row 1 - k
Row 2 - P
Row 3 - inc 2 stitches on either end and k the row
Rows 4 to 12 - k, p, k, p etc
Row 13 inc 2 stitches

OR does it mean to do 32 rows stocking stitch. And then after those 32 rows, start row 1 k, row 2 p, row 3 inc 2 stitches???

Also, when increasing which type of increase is best?

Any help gladly received. Thanks

Welcome to KH!
These directions would be much clearer if they spelled out inc (increasing in this case) instead of using the abbreviation. Most sleeves start increasing near the wrist so it’s likely that you increase on row 3 out of the 32 (your first interpretation).
Can you give us a pattern link or a pattern name?

Thank you; I thought that would be the case but I’ve read sketching similar on another thread on these forums which states starting increase after the first lot of stocking stitch (my 2nd interpretation!).

It’s a Patons pattern vit. Kids Colour Block Sweater, I don’t have a link as its a paper pattern I bought from my local yarn shop. Would it help if I post a photo of that part?

No that’s ok. The fact that it’s a children’s sweater makes it even more likely that your first interpretation is correct. The sleeves are not very long on children’s sweaters.
Good luck finishing and enjoy the knitting!

Thank you; can you tell me which type of increase I should use please?

Just about any of the increases will work. It’s a matter or personal preference.
There are several with videos here.

I like KLL (knit left loop) and KRL (knit right loop) because they blend in quite well.

Thank you once again. And sorry one more question - when it says …then in every foll 10th row…, does that mean that after the 3rd row I count again from 1 and then on the 10th I do the increase or does it mean that the 10th includes the first 3 I’ve done already ie the 7th row after the 3rd???

Because it says every [I]following[/I] 10th, you’ll increase on 3 then 13 and 23