The art of mixing patterns is not as complicated as it looks.
Color, color and color, use a color and repeat it in different patterns.
Via http://www.ruemag.com/ Photo Kimberly Genevieve
Interior Designer Kathryn Ireland is really the queen of mixed patterns. In her living room she is using coral in different intensity, from lighter to darker coral and a creamy sofa as a solid color base.
In her bedroom she is repeating the color coral and the solid color ivory but this time with a mixture of patterns, flowers and stripes, small patterns, bigger patterns.
A room decorated with mixed patterns often looks like it has been thrown together by accident, but this is no accident, as you can see the wallpaper pattern is repeated in the fabric of the bedspread, and the pillows. The ivory neutral color and the coral are always present and create a continuity from one room to the other.
http://www.housebeautiful.com/Photo James Merrel
A few shades of green mixed with a more neutral solid color. Be daring you might enjoy it, mix your patterns have no fear.