How you do create the illusion of longer legs? Go high waisted. Visually you will look like you legs start wherever the waist of the skirt or pants start. Of course adding high heels will elongate your body and your legs even more.
Don't break the line from your waist to your feet. I've kept everything grey so visually it looks like one long solid block of color. Also make sure that your shoes do not come up too high on your feet. Boots or shoes that have straps coming across the foot will visually cut off your feet and make you look shorter.
My ever present stylist Zoe is taking one last sniff to make sure everything is "just so" : )