How the hell do I study for H2 Economics.

I'm actually so screwed for econs. Promos are like 2 weeks away and I can't seem to have enough time? To understand and study 3 whole books of econs. If I do notes I won't have so much time to actl practice qns. Some ppl recommend just writing down an overall overview for the topic and then the details I can learn how to write them in my practices. Do y'all think this wld work? How should I approach this?