Noting meditation and other techniques - help

[Joscha]

I have been doing meditation on and off for a while but decided I wanted to delve deeper into it. So I got "mastering the core teachings of the buddha" by Daniel Ingram. 

He emphasizes a technique called noting in which you mentally note arising sensations. Multiple per second. He says every in breath we note "rising", every out breath "falling" and everything in between we note as fast as possible.  He also gave an analogy about shooting aliens (which can be any sensation/object in awarness I guess)  like in a videogame, but shooting them means noting them. It was very stressful when I tried it. I thought meditation is peaceful, which is why it confused me. Maybe this is the difference between concentration meditation and investigation meditation? 

I wanted a technique to work on awakening. He says awakening is basically getting insights into these three areas: impermanence, suffering, no ego. Do you know any techniques which achieve this effectively? There are multiple techniques I know but I don't know now what specifically they are for.

For example:

- Observing awarness itself

- Being aware of the sensation of self wherever it is (for me in the back of my head) for a long time  (is this basically self enquiry?)

- Nothingness technique from Leo (I think)

- Bringing awarness back to breath after thoughts arise technique. 

And of course just simple concentration techniques, which I like most because they are so simple. I'm just really confused right now. I really kind of hate the noting technique. (is it the same as "labeling", just a different name?) but maybe Im doing it wrong.  What are the techniques I listed for and can they be used for enlightnening? Are there any others you could share?