'Holistic' means to embrace the view "the whole is greater than the sum of its parts". Being psychic requires to a great degree to assume and use a holistic view of the world. Despite that, not everyone is a holistic psychic.
Psychics who claim that they got their psychic abilities through talent rather than spiritual work often turn out to be not very wholesome. They are specialist who are familiar with only their little corner of the psychic world, and their psychic ability can be a curse as well as a blessing.
A holistic psychic does his or her best to look at the big picture. Analyzing (breaking down) parts and aspects is fine and useful - but only if you can put it together again so that it makes sense to you as a whole.
Because of this, one of the main tool of a holistic psychic is the ability to 'zoom in' at a particular level of psychic energies, and identify the tiny obstacle that can cause the greater whole grind to a halt. It generally manifests as a simple "Aha! Of course" moment. Without this basic ability, the psychic realm can feel like poking in the dark.
How to be more holistic?
Do your best to look at the big picture. When you come to understand parts of something, don't stop there. Observe how things relate to and interact with other things. Try to follow primary, secondary and tertiary results of an action. Most importantly, find a way to personally relate to the dynamic world around you and integrate it within yourself.