Four readings, all in common use
Literal: a real force that can be built up, held and directed. Will and intention: a concentration of purpose, with the language of energy as shorthand. Psychological and symbolic: a deliberate use of arousal, rhythm and focus that changes the practitioner rather than the world. Mixed: most experienced practitioners, honestly, sit here and don't spend much time on the metaphysics. Pretty Little Wiccan does not tell you which is true.
How it is commonly done
Repetition and rhythm: chanting, drumming, clapping, breath. Movement: dancing, rocking, walking a circle. Sustained focus on a single image, phrase or object. Building tension deliberately and then releasing it at a chosen moment.
Directing and releasing
Whatever you think is happening, the shape is the same: build, hold briefly, release towards the purpose you named, then stop. The release should be decisive. Trailing off is what leaves people feeling jangled afterwards.
Afterwards, ground
Eat something, drink something, put your hands on the floor, notice the room. Feeling wired, tearful or exhausted after intense repetitive work is well documented and is not evidence of anything supernatural having gone wrong.
Sensible limits
Hyperventilation, prolonged spinning, extreme fasting and sleep deprivation are all traditional shortcuts to altered states and all carry real risk. None of them is necessary, and this app does not teach them.