When you have created a lot of personal iTunes Radio stations, you may find that they’re not in the order you like. No problem; you can change this.
In iTunes, just click and hold a station, then drag it where you want:
On an iOS device, go to Music, tap Radio, then tap Edit next to My Stations. Tap Edit on the next screen, then move a station to the location you want by tapping and dragging the handle to the right of its name.
Remember that the order of your iTunes Radio stations syncs via iCloud to all your devices. So if you move a station in iTunes on your Mac, its position will change on your iPhone. You can’t have different station organization on different devices.
Update: a reader wrote to me saying that he was seeing different iTunes Radio stations on different devices. I suggested that he log out of the iTunes Store on all the devices, then log in again. This solved the problem. So if you’re not seeing all your radio stations, try that.