Having two babies to potty train at once is not a bit fun. Mind you, in the beginning, I was calm and let them do what they wanted when going potty. But then, they both took to going potty as if it were a game.
I have to remind them, "This is not a game and if you fall down while on the potty, you will hurt yoursefl!" Then, they both love the be in our small bathroom, at the same time, watching each other and they always want Mommy to "Sit down" and watch them.
After they do their deed, or lack thereof, the pick up their stepstool and move it under the sink to wash their hands.
As of today, they still are not potty trained.
Last week, we went to Tar'get and purchased some underwear as an encouragment for no more diapers. Did it work? NO! Once in their underwear, they stopped telling Mommy they had to go potty and guess what? That is right, they peed in the underwear and on the carpet or hard floors.
So, it looks like we are back to square one.
Maybe once they are a bit older,they will grasp the concept better. I will give them until November, their birthday, to see if they will understand more.

Potty Training
Potty Training Suggestions
My sister, who does not have twins, has been giving her boys treats, like M&Ms or Jelly Beans as a reward. I think I will begin doing this as well. I just need to go to Wal Mart, purchase a container and a bag of M&Ms.
This is sure to be an encourager of using the potty correctly, right?
Good Luck !!
Tips for Potty-Training Twins
There's an article here on TwinsTalk about potty-training twins that might give you some ideas. Here's the link:
http://www.twinstalk.com/twinstips/taking-agony-out-potty-training-twins
I hope it helps!
Susan M. Heim is the author of It's Twins! Parent-to-Parent Advice from Infancy Through Adolescence and Twice the Love: Stories of Inspiration for Families with Twins, Multiples and Singletons.