Boredom. I'm not always bored when procrastinating but I get bored very easily while procrastinating. The thoughts/feelings that arise go something like: "what do I do now - I've already done everything - oh god bored - hey wait a sec - I'm just spinning uselessly - I'm procrastinating".
That's as opposed to boredom while not procrastinating, which often produces something like "erm, why isn't this over - oh god bored - can I just be done? - what's interesting to think about while doing this?". For example while driving or biking.
Much of my recent experience of procrastination has actually felt like rationalization. That is, I know that the task I'm about to do isn't the one I planned but I still feel I'm able to justify it somehow. So some of the cues listed under Anna's post might apply here too.
I feel tension.
When I am not procrastinating, I am focused on what I am doing. Whan I am procrastinating, there is usually the feeling that something is wrong, which makes me tense -- sometimes the feeling goes aways in a middle of the alternative action, but it is there at the beginning, and it will return when the action is over.
Just make it a habit to ask yourself certain questions. Am I being productive? Am I happy with how I spent the last 30 minutes?
It would make a nice phone app. A random in time chime, with a question prompting for a yes no answer. Am I being productive? Knowing that the question is coming may motivate better behavior, and plotting the results would give appropriate feedback.
Late in the evening I create an agenda for tomorrow's day. I usually have a good idea of how much free time I'll have, and how I should spend it. If the next day I didn't accomplish what I wanted, I'll look for a reason. Sometimes it's because something urgent came up; sometimes it's because I actually didn't have to do the tasks I thought I did; but most of the time it's because I didn't use my time efficiently. That's procrastination: follow luke's advice. (Note: it's rare when I didn't get everything done because I put too much on my agenda, but if that happens, turn it down the next time.)
In the moment, I feel procrastination when I'm not looking at my computer screen (or whatever object I'm are working with), when my focus is somewhere else. I think most people call it spacing out. It takes me about a minute or two to catch myself doing that. As soon as I do, I guide my attention back to the computer. (Usually this happens right after I finish doing something, and have not yet decided on my next step.)
Here are two complementary methods that work for noticing I am procrastinating.
Method 1: Train yourself to frequently ask "what should I be doing?". If the answer is different from what you are currently doing, it is quite likely you are procrastinating.
Method 2: List activities which you know begin procrastination (browsing back to the same news site you've already visited three times today, looking for games to play, checking the TV schedule, checking which friends are available for chat). You can do this while thinking back to times when you know in retrospect you were procrastinating, even if you weren't aware of it at the time. Just making yourself aware of these activities should cause you to notice when you are performing them, giving a hint that you might be procrastinating.
The key with method 2 is catching the moment you begin procrastinating. Method 1 helps figure out the cause.
After thinking about this for a while, I can't really come up with any. I feel like the only way I've been able to notice it recently is that I've thought about it consciously and explicitly. Then when I was procrastinating later, I realized it by association. It did feel like I got my foot into the door of a feedback loop, where the more I associate procrastinating with explicitly noticing it, the more I notice it.
I'm going to steal Anna's idea and change it to the instrumental side of rationality. In Luke's algorithm for beating procrastination, Step 1 is to Notice You Are Procrastinating. I'm not so sure this is easy. For me, the knowledge sort of fades in and out without being explicitly grabbed by my consciousness. If I actually held onto that fact, the moment that I was evading a task, and made it clear to myself that I was doing the sub-optimal, and the consequences involved, I think it would go a long way towards getting me to actually get things done.
What do you use to catch it? How do you notice you're procrastinating? Leave your ideas below (one idea per comment), and upvote the comments that you either: (a) use; or (b) will now try using.