I often take kittens from the street who've been abandoned by owners who cant afford more cats or the mothers were killed by cars.
I usually use skimmed milk since regular milk is just really bad for them. I warm it up and feed it to them with a dropper or baby bottle. I wrap them up each night and keep them warm. And wash them once a week and daily with a damp rag since they're not to well kept at birth.
I often find that cats i've raised from birth are smaller and tend not to know how to meow correctly. They're meow is have a meow or sounds like a dying motor lol
But they'll be raised with human personalities. Mine for instance will hug me by laying on me and spreading her forearms around my neck and pressing her face into my cheek for a kiss

its cute and im thankful i raised them each time they do that