To read the first parts of this series, go here.
I think the most important thing you can do to make it possible for you to come home is to be content with less. We live in a very stuff and entertainment driven society. Our houses are packed to the gills with clutter and we spend lots of money just to keep ourselves entertained. Sadly, this mentality causes us to miss out on really living purposeful lives and devoting ourselves to things that are truly important--like a good relationship with the Lord and the people who matter the most to us.
If you're going to choose to part with a big chunk of your income, you'll have to evaluate your spending and figure out what things you can cut out. There's nothing wrong with spending money you have on stuff and entertainment and conveniences, though it is important to examine priorities. If things that are truly non-necessities are keeping you from staying home with your children, I would submit to you that perhaps your priorities are out of line.
Look through your purchase history next time your bank statement comes in the mail. What things do you spend money on that your family really could do without? Could you go down to one car? Downsize to a smaller house? Cut cable TV, or text messaging?
There are also several expenses you won't have if you are staying home: daycare for your children (which can be astronomical!), business clothes for you, lunches out while working, fewer convenience foods since you will have more time to cook from scratch, less wear and tear on your car since you won't be commuting, among many others.
Most importantly, be sure to consider what you are giving up to have the things two incomes can buy. Things have no eternal value. They won't matter a bit once you're gone. However, investing your very best into your families can have a greater impact than we can begin to imagine. That's why, for us, the cost of sacrificing the time I have at home with our daughter (and pretty soon, our son too!) is far greater than we are willing to pay.