A single striking picture is satisfying. A set where every image clearly shows the same person is what makes your work look polished and believable. Consistency is less about luck and more about a few simple habits.
Use the same trained character every time
Always start from the same trained character rather than describing a face from scratch. The training holds the likeness, so let it do that job and keep your descriptions focused on the scene.
Keep a short fixed description
Write a few words that describe the look you want, such as hair, makeup and overall style, and paste them into every picture in the set unchanged. Small differences in wording can drift the look more than you expect.
Change one thing per picture
Vary the pose, the setting or the outfit, but not all three at once. When too much changes together, the character can start to change with it.
Keep the light similar
Faces look very different under warm lamps and cold daylight. Choosing one kind of light for a set keeps the skin tone and features steady from picture to picture.
Keep the background family the same
A set feels like one shoot when the places look related: the same room in different corners, or one style of setting throughout. Jumping from a beach to a dungeon to a kitchen makes even a perfect face feel like three different stories.
Pick the set together
When you choose which pictures to keep, lay them side by side. Drop any that look like a cousin rather than the same person. A smaller set that is clearly consistent always looks better than a larger one that wanders.