How to change from Standard to Itemized Deduction on AR state return?

You'll need to delete and re-enter your Arkansas information. To do this in TurboTax Online: 

1. Select Tax Home in the left pane
2. Select the dropdown on the right side of the State Taxes box, then select Start, Continue, Edit or Review/Edit
3. If the You've already got a head start on state taxes screen appears, select Let's get started.  Otherwise, in the left pane, select Prepare State
4. Proceed through the screens until you come to the Status of your state returns screen
5. Select the trashcan to the right of Arkansas.  On the popup screen, confirm your deletion
6. Back on the Status of your state returns screen, select + Add another State, and select Arkansas
7. Proceed through the Arkansas screens, making any entries necessary
8. On the Ready to Review Your State Return screen, select Continue
9. On the Let's make sure everything is accurate screen, select Fix Return
10. Proceed through any screens, making any corrections or updates necessary, until you get to the Check This Entry screen with Standard and Itemized Deduction options.  Select the correct option

See the screenshot below. 

If you're using the Desktop version of TurboTax, the process will be similar.

Thank you for your reply. I am using the desktop version of Premier and those options are not available. I am not even able to locate a Check Entry screen. There is also not a trash can next to Arkansas in the state return section. The only thing I can do there is add other states. How do I make this change in this version of the software? Thank yoU!

I figured it out! You have to go to Forms > Info Worksheet and make the selection there.