Front light: In order to get front light outside you need to be out there early in the morning or late in the afternoon. You want the sun to be low so that it bathes the face of your subject evenly. It will also allow you to capture more color and detail in your background.
Side light: Placing the light on the side of your subject allows you to be out when the sun is higher and brighter. You can have your subject looking away to eliminate squinting and shadows on the face. You can also get a lovely glow on the parts of the subject you want to highlight.
Full sun: There is no reason to fear full sun. There are times it will be exactly what you want. It can be vibrant and colorful and wonderful. You don't want your subject looking directly into the light of course. Expose for your subjects face and let the background be bright and happy.
Or use it to create an angelic glow, or a hazy, softly lit background.
There are so many possibilities. The best way to figure out your favorites is to get out there and take a ton of pictures! Make some mistakes. Try some crazy things and see what works. Have fun. Get out there and see the light!