The key to living a long and varied life it seems is to shrug off your habits and interests every couple of years (decades?) and learn to do new things, and/or learn to do things differently. This would of course have the effect of making you a jack of many trades rather than a master of one or two… a small price to pay though?
Want to live forever? Break your habits. Do things you don’t know how to do and foreswear the routine. Walk where you would normally drive. Crawl where you would normally walk. Make a friendship with someone in a new language. Put down that cigarette! Or take up that cigarette! Leave your marriage. Give yourself over to something different. Make yourself a beginner. If you do this, each day will become an eternity. You won’t live forever, but it will seem like forever.