Sounds familiar :'3
But here is my advice that might help? Even during scholl I started adopting a system of tracking/planning my activity since I always know there are things I have to do or want to do, but once I have free time it all just goes poof (except art, I always do it in smaller or larger amounts, having to fight myself to study when I want to draw XD BUT studying art in an amateur level is not something I am too good at since ehhhhh I kinda put it in a corner or expect too much in too little time and stuff-I think I'll manage to overcome it and really study how and why and thenicue in art thou ^^ cause I think I tried 2 or 3 times and each one failed pretty quickly, but I think I finally managed to get in a right mindset to pull of a consistent thing, like start with those humans no matter how awful they look every time :'3 I just need to try and learn, plan is to throw caution to a wind and just do it {cause I am thinker not doer and that doesn't give results often, heistation is my middle name, unless I am running on 4 hours of sleep which is not often} I'm gonna study and draw those awful 30 pieces, one a day for a month, and there is no other goal then to do it-quality or imporvement are not the aim here, being persistent is ;3 once I manage to be persistent I can go for improvement part, although I don't plan to half-ass it all, like I know some days will be bad, but on good ones I'll study references and anatomy, so once month is over I will earn persistency and some beginner knowledge).
Now that I gave you my "short" example of something unrelated or maybe not?
I have this notebook (thou I never write down huge secrets or plans, cause it doesn't feel safe) in which I used to put weekly-study plan in every Friday evening-where I would mark exacpt pages and time in which I'll do those things (I did well on pages, but I often needed more time than predicted, but knowing how much time you need for certain activity is probably a skill I have yet to develop) and which subjects of course, I put down 10-30 min brakes too, and also at least 2 hours extra cause I have obligations other than studying too-all that didn't work perfectly, but it was better than before ^^ so I count it as win for now ^^"""
I also use it to make Next Day Plans-like each night I write what I have to do tommorow-not everything, but a priority list and I will see how much I'll manage starting from most important thing of course (thou internally I don't like it, but avoiding stuff is not the way so, why do one important thing when you can do 100 minor ones in order to forget about big important one :'''3)
I also try to put in each night 3 things I did well and 3 that need imporvement-this try is cause, ummm, facing reality of me is not the easiest, but I do okay with it.
Why having written plan helps me? Cause that way I don't have to go through cycle of:
1.what am I supposed to be doing
2.how to do it
3.we are already tired on that step :'3
4. oh no, we need to search for books and then tools and then get alarm going and I need to do this and that and do I have time to do it all?
So in order to remove as many steps that can either tire me out or discourgae me I try to have ready,set,go enviroment already prepared-like if I want to study math in a mornning before school I will leave my desk tidy with materials I need on it, also mark pages I'll study and pencils near, and place to put my phone at once I turn off an alarm. With that I can't make excuses like "it will take me 15 min to get started till I find books and lessons and pencil and get comfortable" which is usually even more dramatic cause they are not in mix, but follow one after another so it looks like it is 5 tasks instead of 1. I can't make excuses cause everything i ready and I just need to sit down and go-so I do :3
I like preparing in the evening cause I have less energy at the time which seem like a good time to do lesser tasks that require little brain power.
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If you want to do something put on paper what you need to do in order to achieve it and once you break it down (and see all things that might be on your way) do one thing at the time (and try to remove as many obstacles you detected as possible; I here make sure I don't give myself too many options in which I can make and excuse or postpone stuff)-if you want to for example go outside for a walk prepare the evening before by deciding a clothing and putting it somehwere visible, prepare bottle of water and food if you want to have on a walk and put it in a backpack along anything else you might need that same evening, so once you wake up and see on your plan "morning walk" you already know all you need to do is get dressed and get backpack and you are ready to go.
P.S. in a future I'd like to have 6 days of a week planned so I can be more disciplined, but in order not too make myself trapped by it I think leaving 1 day a week totally blank in planner could be a good way to balance it out :3