The Three Rules of Tonal Phrasing
From Stanley Hasty

1) Line goes up - volume goes up, line goes down - volume goes down; OR the reverse

2) Tension-release. Emphasize the tension

3) Change of position. In the same chord, emphasize the first and/or lowest note.

Remember: Artistic absolutes only exist in a cultural context.

With various combinations of these rules, you can get 99% of your phrasing ideas in tonal music. It is important to remember style, and to research the historical and composer-al context of each piece as well. Often these rules can be in conflict, and which to emphasize more than the other is up to you and what you're trying to say with the music. These rules should be applied on a micro and macro level, even simultaneously, because there should always be many layers of music happening at once.
#1 is pretty self-explanatory. #2 is mostly for cadences, where you emphasize the tension (usually a V chord), and diminuendo the release (usually the tonic). These diminuendos must be prepared with crescendos in most cases, and the point at which they peak is what I call "the point of maximum tension." I use maximum because phrases often have more than one point of tension. #3 is very much like #2, except that it deals with portions of phrases that are single chords (or arpeggios). For example, given a slurred one-octave ascending leap in a melodic phrase, rule #3 would have you stretching and playing the lower note louder than the upper note that follows.