Preparing the changing area: you have to choose a place that is safe and clean. Then you have to prepare the tools that you will use because it is not safe to leave the baby un-attended to go get a tool that you forgot to prepare.
Unfasten the old diaper but leave it in place because air can make the baby let go one more time.
Hold the baby from his heels and raise the bottom a little bit, then wipe all over the bottom and inside of legs with wipes. After you make sure everything is clean remove the old diaper and set it aside and put a new diaper under the baby
Use anti rash cream between the legs and buttocks and at the genitals.
Fasten the sides well. For a newborn you can tilt the upper part of the front side down a little bit to give room for the umbilical cord and clamp. Take the old diaper and make it into a small ball and toss it in the garbage pin.