I wasn’t a happy trooper when my little brother arrived on the scene, looking like a cross between a cherub and that Farex model. Or, so mum reports. Apparently, I perfected my ‘ice princess’ routine on her and ignored the li’l spotlight-stealer for about a week. And then when I did deign to grace him with my presence, I... er, bit him, much to the mater’s consternation! Luckily, when he and his wife decided to have their second baby, their firstborn wasn’t as notorious as her godmother. Mind you, this only happened because they listened to Grandma and prepared Aanaya about her new sidekick, both before and after the birth.
Show your child her/his own baby pictures (both before and after the new sibling is born) and tell him how s/he acted when s/he was small. You can say that s/he cried a lot because s/he couldn't talk, and mommy and daddy had to pay a lot of attention to her/him. Emphasise that though the baby will take up a lot of your time, s/he'll eventually be a big kid just like the brother/sister.
Appoint your child the baby’s protector. Explain that it’s his job to make sure that people are very gentle with the baby’s fingers and toes. S/he’ll feel important and get the basics of newborn safety.
When you bring the baby home, have someone else carry her into the house and keep your arms available for a big hug. Or arrange for your older child to be away when you first get there so when he comes in, you're settled and ready for him.
Invite him/her to have a snack when you feed the baby, and let him/her hold a book up for you to read to him/her. Store a small stash of treats and books in a spot s/he can reach.