Continue to beat the mixture until it seems pretty homogenous. Since you're using a beater it won't form into a nice doughy ball. You're going to need to use your (clean) hands and combine all of the little bits into a dough ball.
Place your dough ball into a container, cover it, and place it into the fridge for at least 2 hours. I like to leave it in for 4 hours just to be safe.