To increase a Snap Score, the most effective methods include actively sending and receiving snaps, maintaining Snapstreaks by exchanging snaps daily with friends, and regularly posting on your Snapchat story. Engaging in group chats where snaps are sent also helps increase the score since each snap opened contributes to your score. Using a variety of snap types (photos, videos) and consistently using Snapchat over time boosts your score further. Additionally, interacting with Snapchat's new features and the Discover section can contribute positively. Avoid spamming and aim for consistent, genuine interaction for best results.