I don't know how it could be easier: You position inside a word anywhere, press CMD+OPTION+G; the next word is already selected, you can already edit it, no need to bring up Find panel.
This does seem to work but its pretty painful key combination on my mac keyboard.
Or double-tap Command+D.
This doesn't seem to work well as it highlights multiple instances of the word I was on. The current instance and the next instance(but not all instances).