As for the author of the article I've never seen a clear proposal but it appears the idea is to do repeated measurements that display quantum effects while reducing noise as much as possible and check if there are deviations from quantum theory.
EDIT: found a more concrete proposal http://backreaction.blogspot.com/2013/10/testing-conspiracy-...
Besides to put a person in a superposition may require a machine as large as the universe, so you get issues with the speed of light.
The only way to test MWI is multiverse immortality - many worlds means you should expect to always have some future experience - there is no real death.
EPR experiment does exactly that. In fact, it's a good experiment to get intuitive understanding of MWI.
In standard QM says the measurements should be completely uncorrelated, but she argues that in a superdeterministic theory results somewhat correlated.