How do I reset the idle on car once I have changed battery

I changed the battery in my car this afternoon after several difficult starts and having the battery quality checked. Now since changing the battery the car is idling very very rough. I was told by one of the workers where I bought battery that I may need to reset idle. I disconnected cables then after reconnecting I allowed car to go thru different gears after allowing them to stay for at least one minute each then did the process all over again this time with the ac on. However the car is still idling rough. I should too mention that I took the car for about a ten mile drive as I was told that also may reset the idle. Now I am at a loss as to what to do because the car keeps trying to stall with every start up and every time I make a stop. Any ideas? Thanks