1. Write about what you're passionate about!
Many authors have debated the use of exclamation points in any type of non-fiction writing or writing in general. In my opinion, any author writing a narrative should be including events they are passionate about in their writing. When used appropriately, exclamation points can express exactly what degree of passion or emotion (fear/excitement/happiness/pride) you are trying to portray. See here:
"What a hot and strong grasp he had! ---and how like quarried marble was his pale, firm, massive front at this moment! How his eye shone, still watchful, and yet wild, beneath!" (Pg 338).
2. Use figurative language:
Just because you're writing a narrative, nonfiction or autobiography does not mean that you cannot use figurative language! I find a simile, metaphor or even alliteration can be helpful in creating a vivid image for your reader! For instance, "The woods which twelve hours since waved leafy and fragrant as groves between the tropics, now spread, waste, wild, and white as pine-forests in wintry Norway" (pg 345). Can you guess which figurative language technique I used here?? (Hint: it starts with an "A")! If you didn't guess it, the technique I used was alliteration. I chose this technique to illustrate the cohesiveness of the woods. I describe them as "wild", but the repeated "w" sound illuminates a shared quality that all the trees have that make them part of a collection, or family of trees.