I used a Patons Colorwul yarn (the colors looked fun) and I used a size 7mm round knitting needle.
Cast on 179 stitches. Depending on how long you want the scarf. Just make sure it is an odd number of cast ons.
With the working yarn on the right side, place a marker on the right needle to signify the beginning of the round. In this case I just tied a piece of yarn as my marker.
I did a seed stitch for this infinity scarf, but you can do any pattern you want. For a seed stitch you will knit one, purl one and continue this pattern.
Here, I've done a few, and you can see my marker just chillin'
Continue with the pattern, once you've reached your marker, just transfer it to the right needle and continue the seed stitch.
Once the width is what you want, you'll bind off and your done! An infinity scarf!
The seed stitch pattern.
Finished infinity scarf.
Double up for double the neck warmth.
I know I just skipped over the seed stitch part, if I get time I will make a snap guide on seed stitch! But if you have any questions just ask. I'll try to answer them to the best of my ability.