Some of the things I have done in the past to keep inspired include:
- practicing in a different room
- changing the order of the practice of asanas, pranayama, meditation
- changing aspects within the practice, for example, some days doing lots and lots of sun salutations and no other asanas, etc.
- learning new things to add to the practice, like bija mantras with sun salutations
- using inspirational background music, like mantras