It is relatively easy to cut back on expenses. Every time you think about an optional purchase, think about the 20 year return on that money split between stocks and bonds. You can immediately see the cost in a more realistic context if retirement is your aim.
I also have found a vision board helpful. This has kept me focused on the things I want to do. And I read the Wish List Book by Barbara Ann KIpfer, which helped me get an even more specific sense of these things.
But oddly enough, I gravitated mostly back to the things I got good at when I was working, and with less pressure and more leisure, just continued getting better at them in retirement.
This led to many unexpected opportunities. At 76 I have just re-entered the workforce in a job that enables me to do many things I want to do without imposing typical job hassles.