Colors: Neutrals for the win
Beige, cream, white, light grays, or tans, are all great options for mom, dad, and siblings, to keep the focus on baby. Add interest with accessories like a knit diaper cover for baby or pastel cardigan for mom. Soft and/or muted tones are also great ways to add a splash of color without subtlety.
Stay away from: Bold and bright warm tones like apple red and bright orange, as they are just too harsh for the setting and will not compliment baby's already rosier skin. Light will reflect those colors onto skin when everyone is cuddled close. If those colors are your jam, add them in as accessories!
What about baby?
Photographing baby in a simple onesie or swaddled in a cute blanket, is my #1 favorite approach, mainly because a majority of clothes just swallow newborns.
If you want to try clothes as well, think simple and/or sentimental. Sweet vintage rompers that once belonged to daddy or special little dresses that mean something to the family are great to include in a few shots. Otherwise, just keep in mind that the clothing will look best if it fits well and keeps the focus on baby.
That means no characters clothing, loud patterns, or bold colors. True newborn sizes or even preemie sizes are best for those first weeks; if the clothing is too big it will bunch around his/her face, and just look awkward instead of cute in photographs.
Dress to your home
I know that sounds weird, but you should consider your home a subject in your photographs. I recommend taking a look at your walls, the colors you use, the style of your decor when planning. You'll want your wardrobe to compliment that style
FOR EXAMPLE: pictures with your baby in her pastel purple and white nursery will hurt the eyes if you choose a wardrobe of olive green and black. Yikes. That same wardrobe would look dynamite, however, if your home is full of reclaimed wood, cream walls, reds, navy's, and warm tonal accents.
The movement test
In your session, you'll be sitting, laying, and standing. I'll be shooting from high angles, close up, and far away. Make sure you wear something you are comfortable in. I know that's easier said than done if you've just had a baby, but honestly, flowing fabrics, soft linens, and cozy knits look so beautiful in a cozy home session. When choosing your outfit (this mostly goes for mom) do few checks first;
The sitting test: does this look okay when I'm sitting down?
The bent over test: if I bend over-- like picking baby up from his crib or leaning over the kids on the floor, am I still covered to a point I feel comfortable?
The standing test: do I feel good just being me in this outfit without having to make adjustments with every move?
Other misc tips
Patterns can be great when kept to a minimum. Mom in a soft floral maxi dress or silky robe, complimented by the rest of the family in neutral solids would be a beautiful combination.
Mom in a bold and busy printed maxi dress complimented by dad in plaid and baby in chevron will hurt your eyes. That's an extreme example, but you get the idea - patterns are fine, but reign it in.
Make sure all shirts are free of large logos or writing.
Wrinkles do show up in photos, so please make sure all clothing is ironed or steamed, or tossed in the dryer (I am guilty of this one more often than not!)