You hear this term thrown around more than a baby in a gorilla's cage. It's the thoughts you have about yourself basically. "I am important because my writing is effective" may be an idea my ego constructs. I kinda think of it like my soul is my natural state of being and ego is me when i try to define that natural state of being or the conditions that bring it about.
Don't think of an ego as a bad thing. It's neither good nor bad. It's up to us to define the contents and actions of our egos. Keep it in check and cash out when the times right. What part of us defines our ego? The ego must be modified in between the constant thinking we all do: rolling the dough per say.
Bake it at 4:20 for a hundred and thirty minutes.
The ego is constantly changing and evolving; attaching itself to things and experiencing feeling. We're the driver taking in the details while we enjoy a mid summers drive. Making conscious changes as needed while we navigate the road in front of us.
You may imagine sitting at a train station while trains pass in and out. The trains are like thoughts, coming and going. You can hop on one for awhile but you always end up back at the train station.
You're speaking my language brother. Here's an article I wrote on it:
http://themindunleashed.org/2015/07/the-ego-is-not-the-enemy.html