Here is a pattern for a small shawl- or it could be a large scarf- made with cotton DK yarn using garter stitch throughout and knitting sideways across the work so there are never more than 150 stitches on your needles. The shawl has a neat edging all round which is knitted at the same time as the main body of the shawl.
Instructions are given for one size and gauge is not crucial because fit is not crucial for a shawl.
I used one skein of the yarn specified and you could use any DK yarn of your choice. If you wanted a slightly larger/ heavier shawl you could use Aran or worsted weight yarn.
If you need to break off and rejoin yarn I would suggest you do this at the end of a row as the yarn tails can then be threaded up through the ‘tube’ of the edging.