is easy as pie, Teante! I learned from Cat Borhdi's book, "Socks Soar on Two Circular Needles". There was also an article in Knitter's magazine in about 2000.
For my own use, I cast all the stitches onto one circular needle, and at that point, I find it easier to work the first row of the sock. Slip half the stitches to the second needle. Make certain the stitches are not twisted, and line them up next to each other. I use a crochet hook to catch the tail of the cast-on, and join to the foundation row. Then, I just begin working around the sock, half the stitches on one needle and half on the other. It looks just the same as when one is ready to work the graft at the toe, although there is a larger gap in between. I work all of the leg pattern, then work the heel on one needle only. I know I've seen a tutorial on the internet, but can't wrap my mind around where exactly, at the moment. I'll go scouting, and if I find it, will make another post. Trust me, if you can knit socks on three or four double points, you can easily make the transition to two circulars. I find that it eliminates ladders at the joins, too, because the stitches are worked against the narrow cable, and not a fat needle, so they draw up very nicely. And best of all, I don't have to worry about a lost needle . . . they are completely contained on the work.
Try it . . . you'll like it!