If you mean your hubber score, which is the number located on the lower right-side of your profile image, it would be best to participate more in the HubPages community in order to help increase this score. You can do this by publishing more hubs, commenting on other people's hubs, asking and answering questions, posting in the forums, etc.
If you mean your hub's hub score, which is the individual score of each of your hubs, some of the factors involved in computing this is the length of the hub, your overall hubber score and the uniqueness of your hub. It would help to follow the "need some goals?" at the upper right side of a hub in edit mode, which includes having properly attributed images, a lot of text and even some polls and other capsules.
It's also important to note that hub scores and hubber scores normally fluctuate up and down daily. To find out more about this, you can also check out the learning center guide on this topic. Here's the link: https://hubpageshelp.com/features/Learning-Center-... . Hope this helped.