I think the problem with the word "channeling" having distinct definitions is because, to use a Seth term, we all create our own reality, so we all create it differently! My definition of channeling would be different than, say, Johns, and different than, say, Lynns, because "we" are all specialists {I say "we" meaning everyone :) }
To me, it has been my experience that I have learned these meanings:
*Jane Roberts, who was the first to document channeling an entity she called Seth, was a trance channel.
*Edgar Cayce, who went into a trance and channeled his guide, I believe they called him a trance medium.
*Sylvia Browne, who let her guide Francine take over her body, she called it trance mediumship.
*Esther Hicks, who channels a group of entities she calls Abraham, does not like the term channeler. Abraham, however, describes it as "tuning into a channel".
So, maybe the ultimate definition is everyone has their own channel - whether living or nonphysical - and you can learn to tune into these channels. The question then becomes, what "channels" do you want to "tune" into?
I love Abraham's guide to learning to channel, and I post it whenever I get a chance, because it feels good to listen to. Thank you to whoever put that together with the music. It is short, about 4 minutes, but it definately explains channeling, and how I channel :). (Edit - actually I just listened to it again, and I never learned to meditate, or I should say, I haven't learned it yet!, so I just relax, and breathe, and go up higher in my consciousness)
https://www.youtube.com/watch?v=1ilomKaFyw0
If you have the desire to channel, you can most definately figure out how to channel. If there is a fear there, then you must go through the fear first, and then you will be shown the way. If you follow the trail of that, which is listen to you gut - you will be drawn to particular books or websites or people or whereever your guides are leading you to, and a simple path will be shown - your path.
If you are feeling really good and eager about following your path, it just really becomes a simple matter of following the steps given, as long as you have gotten past the fear part.
Then when you learn to channel, you have to get past the "people will think I'm crazy" part - boy, that's fun.
Then, when you have practiced for awhile, I truly do believe their is a specialist for anything in the nonphysical - I personally get help from a Sky Chef when I really need some help, and that is fun - and you can tune in to whomever you wish to. This is gonna sound crazy - there's that word again - but I asked to channel Michael Jackson and asked him to write a song through me because....why not? :)
That was fun and it definately sounded like Michael. The song came through load and clear, with him signing the song, but all I could type were the lyrics, and I don't remember the tune - darn it ! I don't have a keyboard for lyrics....
Jane Roberts tuned into some famous philosopher and wrote a complete book of his - I don't remember what it was called.
They are all available, you just have to set an intention and ask for who you want to speak with.
It is simply practice, and it gets easier each time you practice.
I learned along the way to set up a specific set of protections that I use before I channel, because that makes me feel good about it, and I always ask to speak to a Higher Guide, no matter who I am asking to channel with - I know that sounds strange, but it works for me!
So, it is all individual as to what feels fun and exciting to learn. If it doesn't feel fun and exciting, then you might be tuning into the wrong vibration to channel.
For me, I have learned I have to raise my consciousness upwards, and I do this in a variety of ways, whatever feels good at the time. I've learned different methods from different teachers - and that is the fun in the journey, because it is fun up there!