Hello, aleguem, and welcome back to JustAnswer!
I find that making a written list of things that need to be done, and in the order of importance, is very helpful. Always referring to your list, will help you stay focused, and if you find yourself 'straying' from the list, you can always look at it to get back to the next important thing that needs doing.
You can promise yourself 'rewards' and breaks after accomplishing a task, so you feel good about it, but when you feel you're doing something 'else', instead of something that needs to be done first, check your list, and move on to the next task.
Adding things to your written list, as they come to mind, is also beneficial, as you may forget to accomplish that thing if you don't write it down when it's on your mind.
I wish you much good luck!
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