You may want to check out videos on youtube of people who had visions or had OBE's of seeing hell or going to judgement. If you don't want to, here is a short summary:

Definately repent if nothing else to avoid hell.

2 top reasons for winding up in hell:

1. Unforgiveness

2. Not putting God first in your life, worshipping or relying on other things instead of God (idolatry)

Finally, the worst thing to say at Judgement time:

"I didn't know what I did caused any harm to others"