I believe the most difficult thing about editing your own work is determining if and when you need to cut text. You may have written the most poetic and harmonic sentences, but if they don’t propel the plot forward and are simply beautiful words strewn together, they probably need to be deleted. Most authors, once they find a sentence or phrase they are totally in love with and feel conveys the perfect sentiment, will sometimes try to make that phrase work even if it hurts the overall story. This is why a professional editor is highly recommended since it’s nearly impossible to be truly impartial to your own work.
When taking on at least the first level of edits, make certain every word chosen has a purpose in the story. Perhaps that perfectly written phrase or paragraph doesn’t need to be cut entirely, but simply rewritten so that it offers meaning to your plot? Or maybe a whole new story is fighting for life?
How do you determine what should be cut? Do you find making cuts stressful or liberating? I'd love to hear your thoughts.