I am a freelancer, who sadly got tied to multiple roles which have all different 'lifecycles'. A response to my team should be rather fast so I am not blocking the work of others for example on the other hand it means to be available while implementing an API in the backend according to specifications is something where I usually sit for up to 6 hours and just code.
I am still trying to figure out to be productive, I did certain excel approaches with hard structured schedules which work great if you're not in a 'leading' position since then you don't have to react to others to much.
So nowadays I try to build structured days:
and than the optional branching starts:
every monday or tuesday
every last tuesday of the month:
every 3nd thursday of the month
every 2nd thursday during the semesters
In between I do like 20 minute guitar playing a day
I already eliminated Facebook and don't have any messenger next I want to limit my daily access time of twitter / netflix / emails to a total of 2,5h so I get more things done. To get the longterm productiveness going.
So I think I am currently still on my way to structure my days in accordance to keep my output in a median as well as not being a total workaholic who work's all week all days.
That's how I am 'productive' at least in theory, life always tends to throw in random events.
Also I want to apply certain habit tricks like setting ridiculously low standards to establish a habit. for example 1 pushups a day for 2 week and than increase it. Same goes for code ... instead of waiting for the great time and the perfect moment.
15 minutes on my side project and leave it. Is it super productive? no but it's still better than waiting 8 months to invest 6h in it. because in total I will get 60h of work into it.
I try a lot of those tricks, also the 'and then' method. Instead of creating something new, I add an and-then to one of my existing habits / tasks. And addressing myself in my head as 'you' not as 'i' because it's proven to work well.
So to answer the question what makes me feel most productive, usually it's finishing something having small goals and treating yourself with something nice afterwards gives you this illusion.
I usually never feel productive until I got the comparison to others. I usually feel stupid, slow and incompetent. Talking to others help to seeing that actually it's not that bad. But the problem with IT is you're usually never done.
But I don't want to get into the meta discussion of what does being productive VS feeling productive could be :) since you asked for feeling.