It’s not the answer you want to hear, but doing more yoga will eventually help you stop slipping on your yoga mat. It’s a huge reason people give up on yoga, but in reality, your hand and grip strength grows immensely in the first few months of a regular yoga practice. That means you’ll be putting more weight on your entire hand, rather than just on your palms, so you can hold onto the mat with more control. In the meantime, get a grippy mat like the ones recommended above or try a yoga towel over your mat.