Don't put pillows, quilts, blankets, and other soft bedding in the crib; ditto soft toys. They're choking hazards. (Your baby will be plenty warm in a blanket sleeper.)
Always put your baby down to sleep on her back: It's the best way to prevent SIDS (sudden infant death syndrome).
Lower the crib mattress when she's able to sit up, and again when she can pull to standing.
At around 5 months, when she can sit up, remove her mobile so she doesn't pull it down.
At around 9 months, take out the bumper so your baby's not tempted to climb on it: She could tumble out of the crib.

Essentials for the Nursery

How you decorate your baby's room won't matter one jot to her for at least the first year, so choose whatever color scheme or theme will make you feel good when you're hanging out there. Just make sure you've got these essentials in place:

Look for rolling casters and adjustable mattress heights. Safetywise, the cornerstone of your baby's room should feel solid (not rickety), have narrow slats (you shouldn't be able to fit a soda can between them), and any corner posts should not extend beyond 1/16 of an inch.
Go for 100% cotton sheets (synthetics can irritate sensitive skin) sheets that fit the mattress snugly.
You can buy a changing table, which should be sturdy and a comfortable height for you, with a place to keep diapers, wipes, and other stuff within easy reach. Or you can convert a dresser into a changing table by topping it with a pad.
A pad that slopes upward on the sides and sports safety strap is a must. (Even if your changing table has raised sides, it's not a bad idea to use a contoured pad.) A couple of extra washable pads will come in handy too.
A glider should be solidly made and move back and forth smoothly (good luck getting your baby to drift off in a jerky chair!). Also make sure that it's roomy (so you can snuggle in it with your child when she's a toddler), fits your body comfortably, and has easy-to-clean upholstery.
Make sure the dangling parts face downward, so your baby can see them. A mobile that's designed to swing out of the way is a plus. Instead of a mobile, you can also buy a toy that attaches to the side of the crib. Either way, pass on flashing lights and loud music. That kind of stimulation does not a sleeping baby make!
Not because your baby will be afraid of the dark, but so you won't have to do wee hour feedings and diaper changes under the glare of an overhead or lamp.
Make sure your monitor's frequency is different from your cordless phone's; otherwise you'll get static, or "cross-talk." (Most monitors are 2.4 gigahertz or 900 megahertz.) Beyond that, pick a model that meets your needs: with two receivers so two grown-ups can listen in on the baby at the same time, for example, or a video version if watching her is more reassuring than simply listening to her coos and cries.
Above all, try to create a room that's cozy and serene. It should be a haven for both of you--your own quiet little corner of the world where you can shut the door on the hubbub of daily life and spend time focused on cuddling and getting to know each other.