I can't tell you what you need to do, but this is my cat sailing career It shows what cats I sailed based on my age and fitness. I will be 70 in September.
I started sailing cats in 1983 on a Catapult, moved on to a Dart 18 in 1988 when my eldest son was old enough to crew. Then in 1997 we moved on to a Dart Hawk. In 2002 I decided that a Spitfire, sailing with a light female crew, would be a suitable move. My son also moved to a Spitfire. In 2008 I decided that I was slowing down, swapped the Spitfire for a Shadow. In 2014, having had trouble a few times climbing back on the Shadow after a capsize, and needing help from rescue boats, I finally returned to my original cat, the Catapult, which has a simple righting system. Almost all my sailing for the last 10 years has been at events where rescue has been available. I am very happy that I am still sailing cats, even though I am no longer at the top of the fleet.