Hello guys! So you personally wish to start feeling energy? An admirable goal! Though, it will be difficult to actually get it down to a level where it is completely passive, but it is more than possible!
You may read Unit 1.2 for feeling energy as well, but this is more so just to answer more questions and such as well as explain it a bit differently...
Now then moving on... To feel energy one of the first methods that you can use is the following... Sit down and begin to calmly breath in and out and just relax all of your muscles, basically, begin fall into a slight meditative state, not too deep, and not too shallow, but once you do achieve such, then we can move on.
Now that you are in a shallow meditative state, pay attention to all feeling you are experiences, the sensation of sitting on your floor (or chair/bed), the air movin around you possibly due to AC, to sensations your breathing is causing.. Now, find all of these mundane sensations and then "ignore" them, and look beyond them for any sensations that can not be described as mundane...
Now then, another method you can possible use is one that i don't fully suggest as it teaches you to rely on your visualization at the start, but it does help. As you get into a slight meditative state, instead of doing the both, visualize "mist" inside of you, any color, and then imagine that expanding out and filling you fully, this is another method, but if it works for you isn't guaranteed.
Now then moving on...
What do you mean by not described as mundane?
Well, for example, when someone stares at you from behind, you feel a sensation like you just "know" they are there normally right? You can practically feel there gaze, it will be like that but a lot stronger and more violent in a way.
Oh, but moving on, I need to add something else... what energy exactly is, as this will help you all more so in understanding...
First off, don't believe all of the crap about energy being a mysterious thing that is impossible to explain, it is not, if you scientifically got at it, it is just another level of particles that are separate from the normal atoms... But moving on, in a simpler terms, it is a particle that is everywhere, in you as well, as you have a energy body that overlaps the physical one, and they are both connected with the "soul". So you could say it is a valuable part of you in the end as well as the environment, But scientifically in a fundamental level it is just another particle that is able to be manipulated by a mind.