I place my stitch marker around the loop that is on my hook after I make the last stitch of the round before I make the first stitch of the next round. Another way is to insert the stitch marker into the first stitch of the round after you have made the stitch. Go with whichever one works best for you.
I used Lily Sugar'nCream Cotton yarn. It is 4 - Medium - Worsted. The size of the cozy might be slightly different if you use a thicker or thinner yarn. You can always add or subtract the number of rounds you do to make adjustments if needed.
The bowl I use in the video about 2 3/4 inches tall and 18 3/4 inches around the top. A smaller hook size will make the cozy smaller and a larger hook will make it bigger. I used medium weight cotton yarn for the one in the video. Thicker or thinner yarn will also make a difference in the finished size of the cozy.
My apologies if I overlooked a mistake while filming and editing this video. Stitches in rounds 1-10 should be sc. Starting on round 11 stitches are hdc. All of the Front and Back Post stitches are hdc.