Always make sure that your ladder is secure. Your ladder should be tied, blocked, or secured in some other fashion to make sure that it doesn't fall. Be careful during cleanup. Once again, with latex paint, you simply need soap and water to do the job. With oil-based paint, a paint thinner needs to be used.
Paint thinners are very flammable and are harmful if inhaled.
Store your paint in a safe and cool place. We all make fun of each other sometimes, asking if we ate paint as a child. The funny thing is most of us did. Little did we know then that eating paint is very harmful. Keep your paint and cleaners out of your child's reach, so it is not mistaken as something else, something edible.