how to repel a bumblebee?

It's gotten impossible to do anything in my yard because of bumblebees. At least I think they are bumblebees and not carpenter bees. I don't get close enough to look at their bellies. I am only ever harassed by one at a time. Is there something I can wear that will make them not want to bump into me? I am already using a scent-free shampoo. I don't wear cologne, and no makeup in the yard.