@mez2113, good point. I confess I have only steeked wool & acrylic. The acryllic was 4 color fairisle, tho & 2 strands were very slick & slippery. After I was done I had worked so hard & loved it so much it became too precious to wear - So I cant tell you very much about how it held up. Im still waiting for a non-food special occasion to wear it to!
There are so many problems with cotton, imo. I love it but it is unpredictable. If you have any yarn left over, knit up the trusty gauge swatch (or use the one you have) steek that (excellent link, @salmonmac ).
Treat it exactly as you will the finished sweater, machine or hand washing. I would recommend drying flat & block it as long as possible in any case. See if/or how much it frays or produces otherwise undesirable results. You might reinforce it with some soft binding tape or the like. I use medical gauze tape - its about 3/8 wide & very soft - on shoulders. (And 100% cotton).
BTW, the thing I hate most about cotton is that so many manufacturers don’t bother to be sure it is balanced & it therefore biases. I love the way it feels on my skin but I find it nothing but a crap shoot to work with. If you find a good brand, be loyal & share the good news!