To start, I can suggest better lighting, remove loose and curling mats and rugs. Also when deciding on a color theme opt for high contrast colors. Go with hand rails in the bathroom. Check the furniture is in good order and if it needs repairs. Make sure her meds are reviewed and not expired. That goes for food items too. Ensure the smoke detectors are working. Try to reduce clutter.
Most accidents happen in the bathroom and kitchen, so concentrate on those areas first.