The best time to prepare for a new job is when you are not looking for a job! Unless you are industry aware in your sector, most hiring managers will give up after 60 seconds during interviews. Looking for tech /strategy job? Read my blog Tekedia.com, Techcrunch, etc. Business job? Businessday, Bloomberg, Fortune, etc. Other areas? Find great platforms that deepen your insights and perspectives.
Do less Facebook cat videos and gossips! Do not think you can use 24 hours to prepare for interviews in a serious companies.
I read The Economist, Fortune, Bloomberg Businessweek, and Forbes (US) with subscriptions paid for years ahead. To work with the top leaders of the world, you must be informed to be exciting to occupy a section of the atoms around them. Because you have no money, the only thing you can command they cannot quickly ramp up is deep personal knowledge base.
The best entertainment to rich people is telling them how to make more money! Unless you have core, they will discover when you are pretending you can help them. Deepen your insights and perspectives through focused and sustained accumulation of knowledge.