I've never made cookies like this before with this type of icing, but watched several videos on how to do it, but the cookies with the straight and plaid lines, how is this done? With an edible marker or something else?  And also, how do you get the effect like in the cookie in the lower right hand picture? do you draw lines with green icing in the white icing while its still wet and then drag with a toothpick? Thanks in advance! :)

Yes, the cookie in the lower right photo is done exactly as you thought. Straight green lines piped left to right while the white icing is still wet and then drag a toothpick up thru the lines and then down, and then repeat. The straight lines and plaid can be piped, but these look like they were done with a marker. It's a very pretty wreath!

I've never had a problem with bleeding when working with wet-on-wet icing. Maybe because all the icing is wet??? I've only had problems when I pipe a dark icing next to a dry light color icing. Wet icing seems to like to leach into dry icing, I've found.

The plaid pattern and straight lines can be done with a stencil and airbrush...you can see a perfect example here: http://www.sweetsugarbelle.com/2013/11/decorated-jelly-jar-cookies/

Thanks so much! and yea seeing those cookies, the wreath cookies do look airbrushed! I don't have an airbrush machine, so I'll have to use what I already have or buy the markers. 

Maybe you can sponge the color on with a brush like this:  http://i01.i.aliimg.com/photo/v0/425185681/Foam_Brush_Sponge_Brush_Art_Brush_Paint.jpg

I also remembered seeing this: http://www.glorioustreats.com/2012/03/easy-gingham-cookies-cookie-decorating.html

So you don't even have to purchase a stencil, you can make one!

A

Ohh good idea! I can't believe I forgot about the Wilton color mists! And I can make my own stencil. Thanks so much! :)