Even though RattVader thinks everybody should know this kinda thing, it is not always easy for someone just starting out.
We would need the type of WDH that you are using...a picture would be good.
On many types of WDH, you need to use the tongue jack to raise the tongue while it is still connected to the tow vehicle. This relieves the stress on the spring bars. At that point, you would remove the spring bars, but that is done differently on particular brands of WDH....that is why we need that information.
After the spring bars are removed, lower the tongue jack to where the tow vehicle looks about level. Pull the coupler latch, unhook the electrical umbilical, unhook the emergency braking system cable, and unhook the safety chains. Raise the trailer tongue again.....make sure the trailer wheels are choked. It the trailer tongue does not easily come off of the ball, you may need to move the tow vehicle slightly and carefully forward (or backward).
Ask any specifics, and someone will be glad to help here.
Chap , DW Joy, and Fur Baby Sango
2006 Ford F150 Super Cab 4x4
2008 Surveyor 263