Don’t worry about the details! I hear this from designers and non-designers, and I can’t get on board! Not having things line up properly as you flip through, Photoshop jobs that have white marks where the edging wasn’t done properly, it is created in the wrong program and now it has to be recreated so it can scale to a larger size, or the website doesn’t work properly on mobile! Make your assets ready for anything and know the possibilities. Look at a different lens… the viewer, not you. There will always be mistakes, growth and learning but care about your work. Every piece! If you care for one design you will be that much better for the next. But if you slack you won’t grow at the speed you could if you cut corners.
Time moves quickly and you could be doing yourself a disservice if you don't try.