I'm not as good at explaining things, though I enjoy sharing information.
I suspect my facility at picking things up is part of why I'm not as good at explaining things myself: since I can get by with a partial or not entirely untangled explanation, I've had less need to create, or figure out what goes into, a really good one.
I can do it on paper. I can't always do it out loud, one-on-one. Being asked questions often helps.