To speed up drying time, place your creation under the sun.
Paint after it's completely dry using acrylic or watercolor paints for brighter color.
Coloring the dough before kneading: mix warm water with few drops food color of your choice.
Coloring the dough after kneading: add food color to the dough and knead it again until the color spread evenly.
Use plastic wrap to keep the balance and put it in the zip-lock bag.
Use water to glue dough pieces.
Other thing to note is this dough a little bit brittle. So do not touch your model too many times during the drying process. Leave it until it's completely dry, paint it and apply a layer of varnish or use spray varnish to protect your craft.