Graduating to the Big Tub
Your baby is ready to graduate to a regular bathtub once he can sit steadily without support (usually some time after six months).
You'll find that baby stores sell bath seats or rings for this stage. These will give your baby extra support, but probably aren't worth a trip to buy them. Your baby won't use a bath ring for long; as soon as he starts crawling, he'll want to explore the tub. A bath ring or seat may give you a false sense of confidence. Even when your baby is in a bath ring or seat, you need to stay within grabbing distance — these devices don't keep a baby from tipping over and slipping under the water.
Your best bet may be to get in the tub with him and support him between your legs. This is a two-person job. One person gets in the tub first, then the other one hands off the baby. (Reverse the procedure on the way out.)
Since a towel or sponge on the bottom of a regular tub will slide all over, get a non-skid mat if your baby seems not to like sitting on the bathtub's hard surface. This will be softer to sit on, as well as safer.
