Soft edges in your photography can be a beautiful effect.  You can achieve the look in a few ways.  If you have a Lensbaby lens, it will do the work for you. You can also use a very wide aperture (low f stop)  and shallow depth of field. If you want to play with vignettes and blurs in post processing, that can be fun and effective as well.  Play with the light and shadows and experiment with focus to get the effect.