When you have a child, the first thing you want to do is purchase items for that child. There are a few things you should take into consideration when purchasing things for a child in the NICU.
First off, that NICU may have its own policy about what is and is not appropriate. Some NICUs allow you to bring in stuffed animals, and some do not because they feel as though they contain allergens. You should check with your NICU on what there policy is, what's allowed.
There are certain stores online that sell clothing, specifically for micro preemies, between one and three pounds. Those first outfits that you baby wears, you can actually purchase clothing that will fit them. Another option is doll clothing will often fit before premature clothing will fit a micro preemie.
Other things you should consider bringing into the NICU are pieces of fabric that you have slept with. If you put that fabric in the isolette, the infant can smell you. That sense is very important for babies. You can also record yourself reading stories to the baby. Purchasing a hand recording and reading stories to your baby, so when you are not there, your baby can hear your voice.
Finally, purchasing a small disposable camera that can be kept by their bedside, allows the nurses and therapists to take pictures when you are not there, so that you can create memories of your child being in the NICU, even if you can't be there all the time.