I got a bit fed up with clicking the little symbol at the bottom right of my screen every time I wanted to switch between the hiragana and English alphabet and found some pretty nifty hotkeys, so I wanted to share. Here you go!
Alt + Shift = Shift between all your keyboard languages options
Alt + Caps = Set Japanese writing to Katakana input
Ctrl + Caps = Set Japanese writing to Hiragana input
Alt + ~ = Switch from Japanese alphabet to English alphabet
I got these from here if you want to look at the other nifty hotkeys. I hope I made your day a little easier.