Casting on for sweater sleeves


I’m a beginner and found this cute pattern but am confused by these instructions : "then cast on 34 more stitches on each side of the sleeve (=104 st)

How can I cast on 34 stitches to each side of a sleeve thats already made? Help please!!!

Do it at the beginning of the row using the knit cast on. Knit into the first st but leave it on the needle and put the new st on the same needle. Repeat until you have 34 new stitches. Work across the new sts and the original ones and you may have to CO sts at the beginning of the next row too.

question I was also wondering if this would work:

I already have 36 worked st on my needle, so if I cast on the first set of 34 st then move (sl the sts over) all the st to another needle and cast on the extra 34 st to make a total of 104 st?

Oh and thanks for the help I’m totally stumped by this I was trying to make lino’s coat on ravelry :

No that’s not what you should do, the new sts should be one both sides of the original sts, making a T shape and will make the front and back. Cast on using the knit (or cable) CO, and you’re still at the beginning of a row. Knit over the new sts, knit the 36 sts and turn. CO the other 34 sts and you now have 104.

Cool beans makes sense now thanks a bunch!