For a 3-month-old baby, it is recommended to avoid exposing them to direct sunlight. It is best to use a hat and clothing that offer protection against UVA and UVB rays. Sunscreen may not be suitable for babies under 6 months old due to their more permeable skin. As for yourself, it is important to use a broad-spectrum sunscreen with an SPF of 30 or higher to protect against both UVA and UVB rays. Remember to clean your hands before breastfeeding and consider wearing long clothing and a hat, staying in the shade, and avoiding sun exposure between 11 am and 4 pm.