A big part of achieving productivity for me comes down to 3 things.
Freeing Your Mind
It is said that motivation can keep you going for about 2-3 weeks. It is also said that it takes 3 weeks to develop a new habit (or break an old one). More succinctly, motivate yourself to develop a new habit. For example, if you want learn a new language, instead of using the time you feel motivated to learn that new language, use that period to develop a habit of, say for example, spending an hour a day to learning that new language. Here's how that change of mindset works.
Learning a new language is a big project, and while you might be making S.M.A.R.T short term goals to gauge your success, it's still something that takes a long time to do. If however, your only goal is to develop a habit towards learning the language, it's little bite sized things that you can digest that you can formulate a habit around. Not only this, but by building this habit, and being able to track the habit, those small little victories not only give you that boost of accomplishment dopamine, but you'll also likely be surprised at how much you'll have accomplished during that 3 week run. And while there's that difficulty in sticking to that habit, once the habit is formed, it's easier to keep going.
There are a number of ways that this can be accomplished. For some people, it's simply a matter of keeping track. There are tonnes of habit trackers available. The method I use is a variation of what they use for Bullet Journaling; a simple spreadsheet in the journal with the habits on top, and dates on the side, using a dot to signify that it was completed that day, an 'S' for days that I skipped for a valid reason (ie., had to go to the doctor's), and a blank spot if it was skipped for no reason at all. This allows me to track how my new habit is forming.
I've also seen people who use a tally method for consecutive days they've been able to continue with their new habit, and then starting from zero again if they've skipped. Another thing that I've seen people do with tallying, is rewarding themselves every time they hit a tally marker, say, every 10 times they participate in this new habit, they provide themselves with a small reward, or a larger reward every 50 times or something. The point is, that it doesn't really matter which methodology you choose, so long as it is one that works for you. Don't think that you have to get it right the first time either. This whole process is about trial and error. The only thing that you might want to consider is, what do you think will motivate you to consistently until it becomes a habit?
There are tonnes of systems out there. Quite honestly, there isn't one that's better than another. The only thing that is important, is finding a system that works for you. Some people want/need something that's highly visual. For those people, a KanBan board might be great for them. Some people are more artistic and want that personal flourish. It's one of the reasons why bullet journals are so popular. That being said, a bullet journal, in it's essence, can be stripped down to function very simply as well. These are but a few of the plethora of options that are available. Find some time to look around to see which system works best for you.
For me, I'm pretty good at organising the big things in my head. It's little things and details that I'm horrible at. So for me, it's really about a 'Get Things Done' (GTD) list, or a to-do list. Every method has its strengths and weaknesses. One of the weaknesses for this one is that it might soon look very long because, well... Life. Things are always happening and there are always more things that need to get done. What I try to do, is just put down things that I plan on doing today. I don't prioritise the items very much, I just pick and choose the next one that I want to get done at that moment, depending on how much time I have.
Along with this to-do list, I also have a consolidated Google Calendar that has every appointment and meeting on it. So the things that I put on my list of things to do for any given day, I look at what blocks of time I have available to devote to getting stuff done. If I have several larger chunks of time, then for my to-do list for the day, I can add a couple of larger items, or multiple smaller items. If there is less time, then I write down less. Sometimes, there are days that a completely full. I usually keep my Fridays open to use as a lieu day in case there are tasks that I've written down that I haven't had an opportunity to complete/get to.
Free Your Mind
In the words of R&B group, En Vogue, "Free your mind! And the rest will follow".
This is something that has helped me immensely. As entrepreneurs and as small business operators, our brains are quite often thinking about our business, even when we're away from the office. To be able to free your mind from these things, to set the issue aside for a little bit; it's a huge benefit.
Some people keep a notebook. I've seen some people keep little pocket-sized ones too. At one point, I had three notebooks for all the different hats I was wearing. But this also meant that I had to either carry around multiple notebooks, or have to insert thoughts that were of the wrong topic into the various notebooks. Organising my thoughts became an act of tedium.
Instead, I've started a list on Google Keep that I've called my 'Repository List', or in other words, my brain dump. I have Google Assistant on my speakers at home and I'm using a Google phone; the latter of which, is connected to my car when I'm driving. So anytime I think of anything I need to do for work, I just tell the Google Assistant to add an item to said repository list. This way, it's been recorded and I can access it later when I'm in work mode again. This is especially helpful for me because I can be fairly absent-minded and scatterbrained. It helps me to remember things for later.
I've reiterated several times that it's really not about evaluating which system is better or worse; it really is simply a matter of what system works for you. Are you someone that needs a lot of structure? Are you someone that would appreciate more creative flexibility to make something yours? Or are you someone that likes to keep things simple? There are plenty of systems for you to pick and choose from. And feel free to mix-and-match too! Sprinkle in a few elements that's purely yours too. The purpose after all, is to find something that works for you.