Once the conditional permanent residency is obtained it has to be your intent to be a permanent resident and spend the majority of your time living and working in the U.S. If you return to your original home you are only visiting for a short period and not being away from the U.S. for more than 6 months. To show proof of of your residency you can buy a house, set up a bank account,
Buy a car, have a drivers license, being a member of different organizations, your children enrolled in local schools, etc.
Besides a residence, you will also have to pay US Taxes. You or your children attending school, or employment in the US will also show your intention to remain in the US. Limiting your visits to your home country (or any trips outside of the US) is an important factor to consider as well.