My van was running and it just turned it self off now it wont start again it just clicks in the fuse pannel

Are your headlights bright or check voltage ar battery with lights on or with someone cranking engine. Cranking not below 10.5 volts. If it is replace battery.Remove terminals on battery and clean. Now go into fuses and replace starter relay with another one in box it usually says spare or remove the same one from another circuit and try cranking engine if it cranks replace relay if it doesn't have someone try to start it and you hit the starter with a hammer hard a few times while it's being cranked if it cranks all of a sudden the starter has a bad armature and needs to be replaced