Asking for help with newborn?

Erin

I'm not sure what the proper etiquette of asking for help is when the baby arrives and there's anything I'm suppose to do it return.

The only person I can rely on is my MIL who is happy to help but I haven't officially asked yet because I don't know what to say and I know she's going to want to over stay her welcome.

Is it rude to ask (for example) that she walk the dog but she can't stay long after? My husband says that would be and she should stay as long as she wants but with catching up on sleep, bonding with baby and learning breastfeed, I don't really want her around 24/7. Advice?