Once learned, you can flow this energy in a matter of seconds by visualizing and giving the intention for the energy to "flow up through my skeletal system, through my brain, down through my endocrine system and up through my chakra system. (take deep breath) And now out the top of my head down and around my entire field." If you do not know all the anatomical areas in the meditation, that is fine, simply give the intent for the energy to go there ... it will.
You may feel the energy, you may not or you may feel it only in some areas. Whatever you are or are not feeling is great - this simply provides you with a starting point. The more you practice this, the more you will feel.
And know that whether or not you can feel the energy it IS working its way through your system. Give the intention for it to flow and focus your energy as best you can. This too improves with practice.
Enjoy!