One of the most interesting features in Finale is playback, which allows you to listen to the music you have just written with the correct instrument timbre. To use it, simply press the "Play" button on the top-left of the screen.
While the makers of Finale has spent considerable effort making their playback sound as close to real life as possible, it is not perfect. Consider playback more a note-checker than a true-to-life recording.
Finale has many ways of optimizing music spacing. If the defaults are not displaying the music to your satisfaction, here are a few ways to manually adjust:
Here are some tips for after you understand Finale's basics: