How do I get the 2 color effect when piping the icing on cupcakes? I want to do pink and green for strawberry shortcake cupcakes.

I take one color of icing and put it into the right side of the piping bag all the way down to the tip and then put the other color on the left side of the piping bag. There are quite a few different techniques to get the same effect but this is the easiest one for me.

There are also partitioned pastry bags for people like me who are uncoordinated and messy.

There are a few ways. If you just want the tip of the frosting another color, you paint a line with food color inside your piping bag and then put in the frosting and pipe.

If you want the same amount of both colors (like when you go get a swirly vanilla and chocolate soft ice cream), you could try doing these plugs with icing and putting both of them into your bag.

http://cakecentral.com/modules.php?name=Forums&file=viewtopic&t=588591

There are also bags and couplers that come divided in two. See the Striper Bag Inserts? You could do that with the tutorial above and you don't have to buy any special bags.

http://www.pastrychef.com/DOUBLE-PASTRY-BAG_p_995.html

http://www.pastrychef.com/STRIPER-BAG-INSERTS_p_1456.html

Or you could use the frosting plug method to get both colors in without buying the special bags.

Questions about painting a stripe of food coloring....If you paint a stipe of food coloring then add the icing how in the world do you get the icing down in the bag without messing up the strip. When I put my icing in the bag it doesn't go neatly to the tip. I have to squeeze and push the icing into place...wouldn't that ruin the stripe?

Here's another vote for the icing plug method. It's awesome for making 2 and 3 toned icing swirls.