Begin with a well-known example of inverted syntax, such as President John F. Kennedy's "Ask not what your country can do for you..." speech.
Rewrite it in conventional English: "Do not ask what your country can do for you."
Think of a few simple sentences to create your own inverted syntax. For example, "It snows in Montana" would become "In Montana it snows."
Use commas to separate the two parts of the inverted sentence, particularly in longer clauses. For instance, "Because he would not be able to find the castle at this hour, he went on to find quarters for the night."
Move on to more complex sentences, taking care not to change the meaning when the structure is reversed.