There are several versions of tubular cast ons. All tubular cast ons give the appearance of a rolled edge. The basic Tubular Cast On starts with half the number of stitches needed. You cast on with waste yarn followed by 4 rows of stockinette stitch in your main color of yarn. Then you increase by picking up stitches from the first row of the main color knitting. This cast on has an elastic edge and is good for K1P1 ribbing used in socks, gloves, and hats.
The Provisional Tubular Cast On begins with the Provisional Cast On before starting the tubular rows. Starting with the Provisional Cast On eliminates having to pick up stitches. It can be used for both K1P1 and K2P2 ribbing and has a matching bind off (Tubular Bind Off).
The Yarnover Tubular Cast On starts with a Chained Cast On in half the number of stitches needed. Yarnovers are used to add the remaining stitches. This cast on is good for knitting in the round and works for both K1P1 and K2P2 ribbing. Most sources recommended using a smaller size needle to do this cast on and prevent flaring out.
The Italian Tubular Cast On is similar to the Provisional Cast On. It does not require the use of waste yarn. You begin this cast on with a long tail about four times the length of what you are casting on. As with the other tubular cast ons this one works well with K1P1 and K2P2 ribbing and matches the Tubular Bind Off.
Links for videos on these cast ons:
Italian Tubular Cast On(flat)
Italian Tubular Cast On (ITR)