Scarf looks like a circle

Hi all, I just learned to knit a few days ago and am trying to do a scarf. My scarf gets wider and wider as I continue, and looks like this ( when I straighten/pull it away from the needle to see what shape it’s taking. It doesn’t come out square like in the videos and pictures. Can anyone please tell me what they think I might be doing wrong? Thanks very much and good knitting to you.

Sounds like extra stitches. A common problem for beginners. Read the Sticky Post about this at the very top of the How to page.

That Sticky Post really helped! I didn’t know I had to purl at all. I suppose I have to make my last stitch a purl before going on and knitting again. I’ve been adding one stitch on each time I switch needles. Thanks so much for pointing me in the right direction!

You don’t have to purl if the rest are all knit sts; that will look odd. You can knit all the sts for garter st. Just be careful when you start a row that the yarn isn’t pulled up over the needle. That makes it look like the first st is two and you’re probably knitting both strands. Pull the yarn off to the side before you begin and you’ll see there’s just the one st.