Scarf on circular needles

Dumb question I’m sure, but I haven’t knit in years. I know I did a huge flat scarf on circular needle. Like 300 stitches. I’m guessing I don’t join my work, but what’s the basic how-to?
Thx in advance

Welcome to KnittingHelp and welcome back to knitting!
That’s exactly right. Don’t join your work. When you get to the end of a row, turn as you would with straight needles, switch the needles in your hands and knit the next row.

Thank you sooo much. I just couldn’t get my head around it!