We home schooled our kids prior to high school and one of the more interesting challenges was this 'doing the steps' part. My eldest was very much like you, look at the problem, tell you the answer. Which was 99% of the time correct, and 1% of the time wrong. She was really annoyed that we focused on that 1% but eventually we got to the point where by writing down all the steps you could then see where in your thinking you had been mislead. The trick was differentiating between "doing math" versus "learning math." (and the nice thing about math at this level is that if you get all the steps right you cannot help but get the right answer). Once we got past the big fight about "always showing your work" not being a 'for all time, forever' edict but instead for a 'these problems while you are learning' edict, it became possible to do math in this ponderous way, but only when learning and only when training our minds on the steps and alerting ourselves to the places we were likely to make mistakes.