Do you mean 2 circular needles? If so, I learned from the link below. You can also get Cat Bordhi's book "Socks Soar on Two Circular Needles". Heels and gussets are easier to do on 2 circulars. You have half the stitches (the instep stitches) resting while you work on the other half (the sole sitches) for the heel. When you're done turning the heel, you just continue knitting all the stitches in the round for the cuff. Much easier than re-arranging stitches on double pointed needles.

Here is a link that might be useful: Socks on 2 circulars

I have been knitting on a single circular needle--48" long. I recently saw a really good demonstration of doing the heel/gussets on the DIY network. Here's a link for that: http://www.diynetwork.com/diy/na_knitting/article/0,2025,DIY_14141_3484730,00.html

Unfortunately, it's a sock knit from the top down to the toe. I'll keep my eyes open for working in the other direction. I KNOW I have bookmarked a couple toe-up patterns...maybe they explain it better. I will let you know.
Laurel

Here is a link that might be useful: heel/gusset instructions; top-down

Sorry for the quick re-post...here's one other link. It IS a toe-up pattern. To change it to 2 circulars, I would just take the 2 resting needles & consider that your second circular...knit the other parts on the one circular needle (like using 2 straight needles) and rejoin at the ankle.
Hope that helps...if not, let me know. I can do some other searching. (Mainly because I want to do this in the future!! It will help ME to have this stuff bookmarked too!)

Laurel

Here is a link that might be useful: toe-up pattern...heel/gusset help??

Hi,
Yeah, me again! When I get going on something...I go! I FOUND exactly what you asked for! The link for the first part is below. At the bottom, you will find clickable links for the heel, heel2, leg & cast off. MANY CLOSE, GOOD pictures....

Hope this REALLY helps!!
Laurel

Here is a link that might be useful: toe up, 2 circular needles, with PICTURES!