Steel caped shoes are recommended, but I think just using your common sense works much better. We always wear a hat of some sort, but it is usually because it is sunny when we are cutting the grass.
Both my husband and I wear glasses, but we still put safety goggles on over those. Actually now we always wear our safety goggles when using any of the electrical stuff. Leaf Blowers, Electric trimmers, and weed-whackers.