Also, don't be tied to the same pattern of beats, syncopation, etc., from one verse to another.
Some songs are deliberately written so that each line in a verse has exactly the same rhythmic pattern as its corresponding line in the next verse, but others aren't.
To make the lyrics sound best, you often have to vary those patterns for different lines, sometimes coming in on the first beat of a measure, sometimes pausing and syncopating, singing some phrases as triplets, etc.
This is a major reason why choral music is often written out over several pages, even though the melody basically repeats throughout.   What will change from page to page in the score is not the melody as such but the rests, the incidentals, the lengths of the notes, etc.   
To me, one of the most annoying things is to hear a song delivered in "sing-song" manner with the phrasing exactly the same from one line or verse to another even though that doesn't really fit what the lyrics are expressing.