Avoiding the dreaded grandfather paradox

I was once again up at five am this morning refreshed and ready to get at it! Contemplating time travel is quite exhilarating and the best thing I've done for myself in months. I've established that one of my characters wants to revisit the past to change an event that ruined his life. Going back in time creates all kinds of challenges for writers that I am looking forward to addressing this daily for however long it takes. I think the best choice at the moment for my time travel novel with be using the "paper" time travel method of transversable wormholes with a resulting splitting of universes that creates a different time track for both causalities. If it is a pre-existing one used by another civilization to travel back further than our hero needs to, then it will work and avoid the grandfather paradox that plagues us!