I think now is a good point to post my experience.
I have been typing on qwerty for close to 20 years now and my average wpm on it has been 50wpm(recently started touch typing). I chose to move to colemak for : 1. Speed and 2. wanted to try out other layouts (safe to say I think I am happy that I chose Colemak) didn't do too much research I knew a friend who used colemak(sykora) so made the decision to use colemak.
So as I was saying I started roughly one month ago. I went the cold turkey approach and landed right on my face. I alternated between layouts. Frustrated that my qwerty and colemak took serious hit and that I was typing really slowly I went back to qwerty and decided that I would stick to qwerty. But then my fickle mind kept telling me not to give up easy so I again alternated for a bit. Past few days I went cold turkey again and have stuck to it. My typing speed is 30wpm but still havent gotten the fluidity that I had/have with qwerty (any ideas how I can do that while I try and get my speed up?).
Also I have a doubt about touch typing: Does touch typing mean that fingers shouldn't be floating?
I am now going adopt a more data driven approach to improve my colemak skills. By doing some typing tests and tutorials online on a regular basis. Also once I get better at I will work on changing the key bindings for vim and some other stuff