Whatever you have to do, will to do it and you will get through the job without becoming negative and so without being tired and without making internal accounts. This is one of the secrets of right work on oneself. Not only that: it makes force in you

Now when you make a real effort or a relatively real effort, you never become negative when you fail. This is a sign. Your failure makes you think more and remember more. But when you make an effort in imagination, an imaginary effort, not a real effort, you become negative very quickly and pass into your gallery of self-pity with all its ancestral portraits.