I have a 1986 Dodge ram 50 that will not start. I have checked the battery it is good.
When I turn the key nothing happens. What should I do.

I have a 1986 Dodge ram 50 that will not start. I have checked the battery it is good.
when I turn the key nothing happens. What should I do.
You say nothing happens? No lights on the dash? Does the horn or headlights work?
Make certain the connection at both ends of both battery cables are clean and tight.
Make sure the fuses are good and that there is no corrosion.

You say nothing happens? No lights on the dash? Does the horn or headlights work?
Make certain the connection at both ends of both battery cables are clean and tight.
Make sure the fuses are good and that there is no corrosion.

Yes all the lights, horn everything works, but when I turn the key nothing. It doesen't even try to turn over.

Make certain the battery is fully charged.
Follow both Positve and Negative battery cable from the battery all the way to the ends.
The cable may have come loose. Test for voltage at the starter positive terminal with a standard test light.
Still there may be an open/faulty ignition switch. If you have an Automatic Trans, test for power through the neutral safety switch. For Standard shift, through the clutch cut-out switch, then make sure that switch's power goes all the way to the starter.
If all that checks good, replace the starter. Got tools?