Okay, Question for Successful IM's (X,XXX+ daily, on average), for whom IM is their main income.
Once you were over the 'learning curve' and hit your stride:
How much time a day / week do you devote to IM and do you work daily or less frequently?
Why the question? I spend 12 - 15 hours a day on a trading floor. I spent evenings and weekends building a website, to create passive income, then realised what I really need is a skillset that is quickly scaleable (and heck IM is Very Similar to Trading). However, I need to know what time I need to commit daily to get serious results (assuming I have the competence to succeed).
Answers / opinions all appreciated....
I work when I don't have other things to do.
I work during the day because all my friends either have work, or university. So typically I'll do 9-5. However I always have my phone with me checking up on things...or for helping out STMers.
I've said this before, you could try work 15+ hours a day. But I bet you won't be productive. I bet you could do that same work in 8 hours.
You can smash big numbers in AM doing your average 9-5 hours. Even less if you are well organized.
There have been a lot of very smart, well-funded studies on the optimal hours per week to work in knowledge work, and I tend to follow those.
All the study results out there boils down to "work a 40-hour (or less) week". IBM did a study in the '80s on this, and before that Henry Ford did a similar study.
Above that, if you keep those hours up long-term, you start to get into negative productivity. Peopleware is an excellent book on this stuff, as is its "sequel", Slack.
In actual fact, there's a body of evidence that says you can be almost as productive working dramatically less hours than that. I know in the past I've experimented with working 20 hours a week, and my productivity didn't drop by more than 15% or so.
But I like my job too much to work on it that little!
The trick is to work smart. I think most people work horribly inefficient (myself often one of them), most worktime could probably be cut in half if you focus, are organized, and have a good workflow/process.
And there's always Parkinson's Law: "work expands so as to fill the time available for its completion". In other words, set goals and deadlines. 
How much I work in a day really varies, some days I feel completely uninspired and decide to quit after 3 hours, other days I get the momentum going and work at it all day.
There's a point where if you work so many hours, that you're just getting diminished returns. Productive output becomes less the more hours you spend.
For me, this usually occurs after 6-8 hours of programming and coding, creative work, etc. I find myself trying to "force" out innovation and productivity.
At that point, it's time to get up and walk the dog.
For affiliate marketing I find the most free time I have during the day, the most unproductive I become.
My best period for productivity was when I had a daily routine.
Wake up at 8 , start work at 8:30 and work till 12:30.
Quick lunch , start work back from 1:30 till 3pm. Then it's gym time + leisure time till 9 after dinner.
2 more hours of work during the evening to check everything and thats it.
So basically if you add up it's 7.5 hours during the day. During this period I managed to get a ton of stuff done.
Having a routine + a clear list of todo stuff did wonders for my productivity.
It's a matter of working smart vs working hard. They're the same and different.
You can work smart and hard at the same time. Putting in 8 hours a day of very efficient work and campaign building. Which is what i did for years.
Now i work usually 11am-5pm, and sometimes 7pm-11pm. I still take my job seriously and work "fulltime" as long as I'm not traveling.