There's some guidance in a couple of the posts from others in another thread with the same title as this. Basically, get Odin, download the right version from Sammobile, follow the instructions to install and keep your fingers crossed.
I bought the exact same model, in the US as well. Currently using it in Australia on the Telstra Network, and with the new update, the IMS Service Stopping message has come up. What is going on? I can't use my phone now????