Unfortunately, it isn't easy explaining how one goes about creating a sentence structure. There is no recipe such as one would follow to make a scrumptious chocolate chip cookie. Of course, it isn't voodoo or magic, either.
Sentence structure is an art form the writer has honed over time. The author has learned to arrange the words in a sequence that encourages the reader to continue from sentence to sentence, paragraph to paragraph, turning the pages to the end. A writer will vary the length of the sentence or the structure.
There are certain rules and parts of structure which the writer can use for effective purposes.
The above give you the word structures to use to create sentences but like a true baker, there is more to it than just ingredients into a bowl. Sentence structure is important. This is the art of putting the words in various arrangements. There are basically four possible styles.
1) Simple Sentence. We learned the simple sentence structure early in school as: Dick runs. See Jane? Sally falls. A simple sentence consists of a noun and verb. There is one independent clause.
2) Compound Sentence. They consist of two independent clauses. The apple is red and the grape is purple.
3) Complex Sentence. This sentence structure consists of an independent and at least one dependent clause. Mark laughed when Ruth cried.
4) Compound-Complex Sentence. These sentences must have at least two or more independent clauses and one dependent clause. Dick ran and Sally fell when Jane chased them.
There are also four different types of functional sentences that are defined by the usage.
1) Declarative Statement. A simple statement. Rain is wet.
2) Interrogative Statement. This is a question. Why is rain wet?
3) Imperative Statement. A demand or request is made. Get out of the rain.
4) Exclamatory Statement. You express strong feelings with an exclamation. You're wet!
By using the above ingredients, a writer creates their own recipe which is unique to them alone. Just like eating a chocolate chip cookie, sometimes the writer will use a long sentence (a big bite) or a small sentence (a nibble) to vary the structure. The author will use various words (milk chocolate chips, dark chocolate chips, butterscotch chips) to change the structure. Sometimes the writer will start with an adverbial phrase (cookie) or possibly a subject (a chip) or toss in a prepositional phrase (nut) to change it all up. Each bite will be different, yet the same: Delicious.