Just to be clear, this is a post of what NOT to do. Unless you're tired of being so glamorous and would like your mommy-look to evoke more compassion from others. For that, I don't blame you - people are much less likely to help if it seems like you've got it all together.
So, even if you do, you can forever look like you don't in these easy steps:
Wear the shirt you slept in last night. Hey, that's one thing off the list to get out of the house (getting dressed). Now, if you're staying in, WHY would you go and use up another shirt?? Do you ENJOY doing laundry??
Only do your make-up minutes before daddy's supposed to come home. He'll think you were that dolled-up all day. BUT you'll have effectively scared the salesperson who knocked on your door. Win-win.
Never wear something that can't be chewed. Save those silky/sheer stuff for when you're baby-free (like, almost never).
Flats are your friends. And so are ponytail holders. Which brings us to...
Have baby-friendly hair. None of that curls-falling-in-your-face kind of style. Save that for a date night. At home, the less hair available for tiny hands, the better.
ALL of this will be forgiven IF:
You maintain yourself odor-free. Brushing your teeth and putting deodorant on before starting your day is much like putting the oxygen mask on first before helping your child. People can complain about your messy looks, but never about your smell.
You're decent. The mailman doesn't need to see a model any more than he needs to see your boob. So, if you're nursing, watch the cleavage.
You're happy. It sounds corny, I know, but wearing a smile is the best way to look nice. Think about it: what's more pleasant, a grumpy dressed-up woman or a frumpy - but joyful - mom?