Marissa Peer makes an excellent point about keeping the mind young.
How to remember?
The problem is, what if you mind is tired and keeps forgetting to do new things? I have found that a physical object is the best way to remind myself to keep something fresh in the works.
Use a physical reminders
For example, I'll put a rubber band or bracelet on my wrist as reminder to brush my teeth with the opposite hand. Sometimes I'll pay attention to which foot I start walking with and change it up. (It's excellent practice in mindfulness.) I might attach a bandaid to my arm to open doors another hand. If you are feeling adventurous, try using your fork with your non-favored hand. Use your imagination!
Challenge: Visit 1 new place each weekend
One summer I decided to visit a new place every weekend. It didn't have to be a special place, just a new location. It really made me think outside of the box.
The practice let me to visiting all of the beautiful spots I had heard about for years but never saw myself. I felt like a tourist in my own town! When all of the touristy locations were gone, then I had to get creative and venture out of my comfort zone. It was liberating to push past old routines.
To keep your brain young, feed it new experiences and knowledge everyday!