Using rom CM 10: How to increase app-space?

My HP touchpad says Internal storage: 1.5GB (only 200MB free)
SD card: 11GB (9GB free)

I cant install more apps as it gives an error about space. I just want to have more space for apps. How can I do this in the easiest way possible?

I was thinking of installing the latest roms but I read about some issues so I just want to stay with the rom I have, which is CM 10 (4.1.2).