How does one enter Valhalla?

Well, if you look at the ancient stories a battle death was not required to go to Valhalla. Ragnar Lodbrok for example died in a snake pit, yet in his death song he is looking forward to going to Valhalla. Those who were cremated also went to Valhalla regardless of how they died. We know this from the "Ynglinga Saga." In "Gautek's Saga," we are told of a family that would throw themselves over a cliff as a sacrifice to Odin in order to make it to Valhalla. Many modern Asatruar rely on such information to shape their beliefs so in many cases they are no different than the ancient ones. Others do not believe in Valhalla at all. Still, others think it requires a battle death.