Introducing 3-year-old to new baby

Carol • Living in Beijing. My daughter is almost 8 and my son is almost 4.
Parents who have more than one child (or are currently having the second one), I'm looking for advice or tips for how to introduce my 3-year-old (almost 4) to her new brother who will be born in August. Did you do or do you plan to do anything special when your older children met/will meet their new sibling? Any advice for transitioning into having several children, stopping arguments, preventing jealousy and any other advice or experience is much appreciated!! Thanks so much!!