when i was preparing for labor + birth, all of the guides i found were about what to pack for a hospital bag. a birth center is a much different experience, in that the stay is generally much shorter after birth (only 5 hours for me). so muchhh less packing was needed! i collected a list of the things i actually brought and used to share to hopefully make the packing process a bit easier for you if a birth center is your plan:

Two sets of your coziest bra or swim top to wear for labor/birth: be sure to bring two sets, especially if you think you may utilize either the birth tub or a shower for pain management during labor, as you may end up getting out and you’ll want something dry to change into. I wore this insanely soft bralette and also brought one of these seamless pullover nursing bras (these later became my favorite nursing bras - just be sure to size up). I also brought two pairs of comfortable undies, but found I didn’t need those.
A light robe: to wear during labor + after birth, those first few hours you will want to have easy access for the midwives to check things and for breastfeeding. I brought this one and wore it immediately after birth and then sooo much postpartum.
Something to wear home: I brought a comfortable but cutesy option and these pajamas (same cozy fabric as the robe) and just wore the pajamas home - I would definitely leave out the cutesy option next time, but maybe you will feel more up for a photo op than I did. I wore these pajamas soo much postpartum, size up for extra room for postpartum diapers and go for the dark colors. This is not the time for neutrals!
An extra set of comfortable clothes for your partner: in case they get messy or wet, or just want a fresh change of clothes at some point.
Extras: Soft socks with grippies, a headband, a hair tie, a hair clip, and a hair brush.

An outfit to go home in: I brought a few options because I wasn’t sure what size he would be, or how you’re supposed to dress a baby in the summer (it’s so confusing! will he get too hot walking out to the car? will he get too cold in the air conditioning on the way home? what if he’s giant?! what if he’s tiny?!) Turns out a newborn size bamboo footie pajama is just fine, and likely stretchy enough to fit a big or small baby.
A soft swaddle blanket: This one was our favorite
An oil based balm: People say to put Vaseline on their bottom to prevent meconium from sticking, but we opted for this balm from Motherlove instead and it did the trick. It’s still our go to for diaper rashes, and lasts forever!
A few diapers if you have a preference on brand, we just used what the birth center provided
Anything sentimental you want stamped with footprints: we brought Finley’s baby book (this is the one we have been using and it’s so sweet) and a tie for my dad, he had my sister and my baby footprints stamped on one when we were born, so I wanted to start a new grandkids tie.

Afterease: this tincture from Wishgarden is so amazing for soothing afterbirth pains, I used this immediately after birth and for the first few days postpartum and it was a must have.
Arnica Tablets: discuss it with you midwife, these were very helpful for soothing perineal pain.
Silverettes: if you plan to breastfeed, these are a life saver. The silver naturally soothes and heals nipple damage that often occurs in those early breastfeeding days. I started using them right away.
Nipple cream: I used the silverettes more, but this is nice to have on hand as well. I love this one from Motherlove.
Dermaplast: my birth center had everything I needed for perineal care after birth (peri bottle, diapers or pads, ice packs, etc.) but recommended to bring our own Dermoplast if wanted and this was very very soothing postpartum. Probably not the most nontoxic thing, but the relief it provides was unmatched.

Portable sound machine - my doula played ambient ocean sounds from her iPad the entire time, but this would have been more convenient, plus you’ll use it later for baby. The Hatch portable sound machine is so cute lasts extremely long between charges.
Hot pad or water bottle for pain management like this one.
Stroller fan like this one on the face for moments you feel hot or nauseous.
Water cup with straw and handle (this one is soo superior to Stanley)
Chapstick (this one from Nash & Jones will change your life)
Fine tooth comb - yes, a sturdy fine tooth comb. Squeezing this during labor can be a shockingly effective tool for pain management, I used it the entire time I was laboring at home and it was such a helpful tool.
Affirmation cards: I had my husband and family write some for me on index cards for encouragement
Snacks: be sure to include honey sticks, electrolyte packets (love these pregnancy friendly ones from Needed), and anything else you might like to snack on. I had a few refrigerated snacks I wanted to bring, so I just had those in a bag in the fridge so it would be easy to grab as we dashed out the door.
Comfort items: Speaker, diffuser, any other items you might want, for vibes - my birth center had all of these but in case yours doesn’t

Misc:

Car bag: I kept a sack in the car with a few things I might need for the ride over during labor - an old towel, a trash bag to sit on in case waters break, peppermint oil for nausea, and a few barf bags (ask your birth center if they can spare a few)
Printed copy of birth preferences, if needed
Insurance cards (in case of hospital transfer)
Disposable camera, tripod, anything you might want for capturing memories
Extra long phone charger
AirPods or wireless headphones
Car seat base installed (keep the carseat inside until go time)
On that note, keep the car gassed

Pro tip:

Make a shared iCloud note for your partner with a checklist of any last minute items to grab - like snacks in the fridge, charger, fill up the water bottle, etc. Go time can be exciting and a rush, this way nothing gets forgotten + your partner isn’t bothering you with questions.

This is one of the *over the top* things I did that I actually loved. I made a separate home screen on my phone that was exclusively for all things labor. I wanted it to be so simple to find any important information and utilize any resources. I had a contraction timer app downloaded and ready to go, the Expectful App (where I had downloaded a bunch of my favorite hypnobirthing meditations), and the best part… a widget that linked to a folder of labor related notes like:

My birth preferences: just another place to have them easily accessible.
Labor positions + reminders: where I had important notes about when to go in, ideas for positions, affirmations, etc.
Playlists: I linked the various Spotify playlists I made for labor so they would be easier to find.
Snack options: I brought so many snack options, I wasn’t sure what might sound good, and I knew I may not remember what all I had/want to go look through the bag - so I thought this might be handy to just look at the list so I could ask for what I wanted.
You could also link any important phone #’s, and boundaries you want to send to guests if you’re having visitors, etc.