Regular practice is key. I used to do ab-initio and commercial instruction, checking and testing on light singles of various types. Never forgetting the reality that we were throwing the beast at the ground, I used to get a real buzz from being able to demo and teach these. I also think it gave me a level of competence and confidence in being able to deal with an engine failure which helped my general flying.
I have now "progressed" to just flying twins and (apart from 6 monthly checks) doing only line flying with no opportunity to drop in the odd auto even. I really feel out of touch and am now relying on the very low probability of double engine failure. I can't even go and do some single engine stuff for fun, cos I am tied into a Flight Time Scheme that precludes me from doing other flying. A positive contribution to flight safety- I think not.
TC reminded me of this with his reminiscences.
Enjoy them while you can!