Newborns poop a lot. But, the good news is that breastmilk is water soluble, so if your baby is exclusively breastfed, there is no need to rinse the breastmilk poo before throwing your diapers in the wash. Hooray!
You just need to be sure to run a rinse and spin or short wash cycle before your main wash in the machine. And, since newborn cloth diapers are so tiny, you may need to bulk up your diaper load a bit otherwise they won’t get cleaned properly. You can bulk up your load with hand towels, mama cloth, or OS fluff if you have another kid still in cloth.
Everyone’s exact wash routine will be a little different, as it all depends on your machine, what detergent you’re using, and your water hardness. In general, you should have a short wash or rinse cycle and then a main wash with the soiled setting on heavy.
If you’re using a synthetic detergent, you can use all cold water, but if you’re using plant-based, you’ll need to use hot water in the main wash. Many moms use trusty Tide, but I prefer plant-based and have had good luck with Seventh Generation Ultra Power Plus.
You can find a full list of recommended laundry detergents on the Fluff Love University Detergent Index.