A good way to improve is to study a structured beginner lighting resource, then practice one setup at a time. The most recommended starting point from the community is Strobist Lighting 101, which is widely used for learning off-camera and studio-style lighting fundamentals.

A helpful exercise is to pick one subject and keep it consistent while you change only one thing at a time: light position, height, distance, or modifier. That makes it much easier to see what each change does.

Don’t dismiss your dog as a subject—pet portraits can be excellent practice. If your dog will tolerate repeated sessions, that gives you a patient subject for testing setups, ratios, and light placement. Stuffed animals and still life subjects are also useful because they stay put.

For portraits specifically, the community also recommends Steve Sint’s book Digital Portrait Photography as a strong lighting primer.

In short: use a structured resource, start with basic lighting setups, and practice systematically with repeatable subjects rather than changing everything at once.