Start by building a budget and determine how much each month you can save. Next, treat that savings like it is a monthly bill, never to be missed. Set it up to automatically move from your checking account to a savings account.
Once your balance reaches $1000, move it to a Money Market Account. This will get you a little bit more interest.
Remember to save for a down payment, and closing costs. For the best interest rate, you will want to put down 20%, but some lenders will qualify you for the loan with as little as 3%.