We always come back to these checklists over at Baby Center because they're divided into category by "Before Your Baby Arrives," "Before Your Baby Crawls," "Toddler and Beyond," and they're very thorough lists.
• Before Your Baby Arrives: includes installing smoke detectors, carbon monoxide detectors, making sure you have a fire extinguisher, and taking an infant CPR class.
• Before Your Baby Crawls: includes installing gates at stairs, attaching edge guards and cabinet locks, and turning pot handles to the back of the stove.
• Before Your Baby Starts Toddling and Climbing: includes using doorstops, hiding electrical cords, and never leaving your child alone in the highchair.
Check out the links for a LOT more in each checklist. And don't be overwhelmed- many are repeated from the earlier lists.
(Image: This Old House by Kidco)