Mom (unspayed females are called jills) may react to these tiny strangers with confusion, at first; but it won't be long before she's trying to stow them in her favorite hidey-hole, like your sock drawer.
Baby ferrets (called kits) start out as little pink "worms", about the size of your little finger. You can spot any albinos in a litter because you can't see the little dark eye behind the transparent skin.Pale fur starts in a few days, turning gray by around two weeks. Any time they're awake they "echo-locate" for mom with peeping sounds that quickly become quite loud!
Mom (unspayed females are called jills) may react to these tiny strangers with confusion, at first; but it won't be long before she's trying to stow them in her favorite hidey-hole, like your sock drawer.
Although I've never had a hand-raised ferret try to keep me away from her babies, she may "adopt" any strange hands that wander too close to her nest. Once adopted, a hand is thoroughly cleaned (just like a kit) and prevented from leaving the nest area (just like a kit). You can get bitten during this process, if you aren't careful.
To reclaim your hand, try distracting the jill with your other hand (just out of range) or another object like a squeaky-toy, then slipping the hand quickly away and out of sight. She'll be suspicious, but too late.
If you provide a cardboard "corner" with a little bit of litter sprinkled in it, the kits will practically litter-train themselves. You may have to be fairly inventive in blocking off non-litterbox areas with cardboard and duct tape, or other obstacles, but make sure they have an unobstructed (and short) path to the litterbox area.
Kits don't open their eyes until around 5 1/2 weeks after birth. Just before then, they pass through the "piranha" phase. You'll want to handle them a lot and smack them gently with one finger (while saying OW!) until they figure out that humans aren't for biting.
They're also eating semi-solid food by this time (the tactic is to roll in it, then lick it off your siblings). Mom began weaning our kits herself at about this age (while saying OW!).
From the time they open their eyes, the world becomes a big and wonderful place. Remember, everything can be exciting, or it can be scary. Loud noises and quick movements can frighten a kit, and you really don't want that, at this age.
Babies can be pretty much independent by 6 weeks, but might be better off to stay with mom for "training" for another 2 to 4 weeks. You're still teaching them the rules -- handle them as much as you can for this period and enforce the "no biting" rule.
It's sad, but you can't keep the whole litter. If someone is going to adopt your kits, do your best to screen the person for appropriateness and responsibleness. And do your best to inform them of ferret resources in the area, books or web-sites to visit, etc. And personally, I'd rather have a kit back if the adoption doesn't work out, than to have the person send it to a shelter or ferret rescue organization.