Complex sentence: Before long the WDA was absorbed into the Ulster Defence Association (UDA) and White became one of this group's leading members, being credited with inventing the "Ulster Freedom Fighters" (UFF) covername that helped the UDA to avoid being outlawed.
Split into simpler sentences: Before long the WDA was absorbed into the Ulster Defence Association (UDA) and White became one of this group's leading members. A senior member of the UDA, White was credited with inventing the "Ulster Freedom Fighters" (UFF) covername that helped the UDA to avoid being outlawed.