Finding cruelty-free lip serums involves a few steps. Here's a guide to help you:

1. Understand the Terminology: Cruelty-free means that the product and its ingredients have not been tested on animals at any stage of product development.

2. Look for Certifications: Look for products that have been certified by recognized organizations such as Leaping Bunny, PETA, or Choose Cruelty-Free. These logos on the product packaging indicate that the product is cruelty-free.

3. Check the Product Label: Many companies will indicate on their product labels if they are cruelty-free. Phrases like "Not tested on animals" or "We love animals" can be a good sign. However, be cautious as some companies can be misleading with their claims.

4. Research the Brand: Visit the brand's website or contact their customer service to inquire about their animal testing policies. Reputable brands should be transparent about their practices.

5. Use Cruelty-Free Apps: There are several apps available that can help you find cruelty-free products. These apps have databases of brands and their animal testing policies.

6. Read the Ingredients: While this can be a bit more challenging, it's worth noting that certain ingredients are often derived from animals. Ingredients like beeswax, lanolin, and carmine are commonly used in lip products and are not considered cruelty-free.

7. Choose Vegan: If you want to be extra sure, opt for vegan products. Vegan means the product does not contain any animal-derived ingredients.

Remember, finding cruelty-free lip serums requires a bit of research, but it's a small step you can take towards a more ethical beauty routine.