Ecover: how/when do you use it?

babydontforget

I've heard people talking about using ecover on their diapers to keep them soft, and I'd like to try it. But I see both fabric softener and detergent available, and I'm confused--do I use the softener? How often? At what point in the wash cycle? Or do people who use ecover use it for detergent? 

I'm currently using RnG. Rinse cold. Hot wash with RnG. Two rinses cold.