Ok, jokes aside now...about all you can do is force yourself to work on it. I try to make sure (when work isn't getting in the way, like it did this month) to work on it at a set time daily. That usually keeps me going for the most part.
Exactly what @bgillisp said, procrastinating is the act of not working on something so forcing yourself to do something is the counter-measure. Granted its nice when you can put your all into it but still sometimes you got to power through those moments of feeling "meh." Make sure to cut out distractions to; don't leave the tv on if you tend to get lost in an airing program or don't go on the internet if you know you will start getting lost in the rpg maker forum because its so awesome.
Wow, nothing except "just do it" huh? That's kind of sad. Okay, I guess I can help then.
Set Realistic Goals. It's easy to get excited about doing something, set up time to do it and then waste your time doing nothing because you never made a plan for what to do. Set goals often, adjust them as needs change and as you get a better understanding of the task in front of you.
Make yourself accountable. If you know someone is going to be asking you about your progress or expecting you to do something you're much more likely to actually do it. Procrastination is a way to move the goalpost so that you never actually fail, so by making the goalpost in control of someone else you're a lot less likely to procrastinate. Instead of a method of avoiding failure, procrastination itself is the failure. People don't like to fail, so they avoid the procrastination instead.
Break it down. Oftentimes we procrastinate because we don't fully understand the path to success. If you think all the way through what you're trying to do, breaking the big goal down into small understandable goals you can stop focusing on the huge task and instead just do the one small manageable task right in front of you. The overwhelming becomes simple if you break it down far enough.
Take one step. People have a lot of inertia. If you haven't started it's hard to get going, and if you've started it's easier to keep going. So a lot of times when it's hard to start don't worry so much about what needs to be done and just do something so that you've got some forward momentum. Scribble on the page before drawing, write random words before crafting a story, code hello world before fixing that battle system. It doesn't have to be good or even something you keep. It just has to be a start.
Allow yourself to win. It's very easy to look at your procrastination habits and beat yourself up for them. You tell yourself that you could have done better or could have been faster if you hadn't wasted your time procrastinating. But this is a losing cycle. You end up punishing yourself for successes and only getting the good things when you procrastinate. Don't taint your successes with guilt. Own them. Celebrate them. And then maybe you'll feel like end results are something to work towards and enjoy instead a punishment to avoid.
Schedule breaks. I'm not just talking the 15 minute ones to stretch, I'm talking making sure you have time away from your project. Completely away, no planning, no going over what you did that day, no expectations no nothing. Keep your work time work time and keep your play time play time. Allow yourself to really enjoy it, whether or not you feel it's deserved. If you are consistent about it your subconscious will stop trying so hard to put work in your play time (guilt trips) and play in your work time (procrastination).
Set a timer. Sometimes, no matter what you do it just seems impossible to get past yourself and do something. In this case try setting a timer for a short period of time, like 15 minutes, and say to yourself "I only have to work until this timer goes off". When the end goal is in sight it becomes a little easier to do the things we hate.
Don't lie to yourself. It's kind of amazing how often we lie to ourselves. We think "I'll only do this for 10 minutes" then spend an hour on it. Or we decide that something is out of our control but still beat ourselves up mentally for messing up. Don't do this. Try to be as honest as you can with yourself, so that when you have a project and think "this won't take long to do this one thing" we'll believe ourselves and have an easier time starting, instead of going "yeah right, it'll take forever, better get my me time in now."
I agree with everything Sharm said and I'm glad I do those things too!
In terms of getting in the "zone" to do work I use brain entrainment to help.
Go on the website brain.fm and they have different sounds/music to play for what you're doing. In your case, it would be Focus and then Intense, and set it for 30 mins. See how much work you can get! For me, it changed my game entirely.
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