I simply write as I would normally. Every few words, the app will convert what I've written into text. I'm going to try to see if I can give you a screenshot of the app as it actually works. It's not easy, because way time I pause for a moment to take the shot, the app converts the text.
-- This message was composed with PhatWare WritePad.
Okay, I wasn't able to take a screenshot on my actual handwriting, no matter how fast I was with the buttons, but you get the idea. You can see from the examples below how as soon as I paused for that fraction of a second to try to get an actual shot of my handwriting before conversion, the engine had already read my text and presented several options. Had I not chosen between them, it would have automatically chosen the first option, which would have been the correct interpretation of my handwriting in the second instance, but not in the first.