Just any advice a new user can be given, I guess.
Treat the tools as you would with traditional medium.
The software has its preloaded tools acting as close to them as they perceive it.
IE: I use the basic mechanical pencil for sketching out ideas.
The increasing the size for a darkening an area or using the darker pencil tool.
Then for "inking" using the basic g-pen settings works for me. With using bucket tool or market> milli/felt pen to fill in blacks.
I havent played around with thier screen tones. But I assume its kinda like photoshop where you just fill/select an area an apply the tones to them.