Review the sentence that precedes the one you want to write. Ensure that the sentence structure is sound and that you do not need to link it to the sentence you are going to write. For example, if the preceding sentence is, "Sometimes, she looks fabulous," you may need to use the "And" as a conjunction and link the sentence rather than start a new one.
Write a sentence beginning with the word "And" to emphasize the preceding sentence. For example, if the preceding sentence was, "She wasn't very nice or friendly or accommodating," you could begin the next sentence, "And she also had an awful sense of humor," which not only emphasizes the person's negative qualities, but puts a final touch on it.
Write a sentence beginning with "And" to make an additional observation or point related to the preceding sentence. For example, if the preceding sentence was, "He swims, boxes, plays football, basketball, baseball and soccer as well as leads the swim team," the next sentence could be, "And on top of all that, he's a straight-A student."