The following are key shortcuts for using BalfSlideView and reveal.js.

Key combination	Action
→, PAGE DOWN, SPACE	Next slide
←, PAGE UP	Previous slide
SHIFT + →	Last Slide
SHIFT + ←	First slide
B	Whiteboard
W	Widget Board/White Screen
C	Toggle Notes Canvas
DEL	Clears Whiteboard/Notes Canvas
S	Show Presenter Mode
SHIFT + D	Toggle Dark Mode
H	Goes to the Home Slide
META + P	Show Print options window

In order to use the 'Start Remote' feature, you'll need to download JB Slide Controls from the Apple App Store. Once you have this you'll be able to control the slides using the app from you Apple Watch.