You can never be sure that element will be found, actually, this is the purpose of functional tests - to tell you if anything changed on your page. But one thing that definitely helps is to add waits for the elements which are often causing NoSuchElementException like
WebDriverWait wait = new WebDriverWait(webDriver, timeoutInSeconds);
wait.until(ExpectedConditions.visibilityOfElementLocated(By.id<locator>));