The first step in making a sentence flow is to divide up the passage into the individual units of thought, called propositions.
A proposition is similar to a sentence, but not always the same as a sentence. A proposition is one idea (one verbal idea). The main difference is that a sentence may contain more than one proposition.
I went to the store and then I came home.
This sentence contains two propositions:
I went to the store.
Then I came home.
God so loved the world that He gave His one and only Son.
This sentence also contains two propositions:
God so loved the world.
He gave His one and only Son.
A proposition is a single idea, action, or statement of fact. Therefore, propositions can be separated by finding the verbs and dividing the passage so that each verbal idea is by itself with its skeleton idea and modifiers.
Note that in English, one verbal idea can be expressed using more than one verb.
He should not have jumped.
contains one verbal idea, using three words -
should have jumped. This is only one proposition, because it contains only one verbal idea, even though the verbal idea is communicated using three words.