At this point in my life (mid to late 40s), I have more money than spare time, so for routine repairs I send my bike to my LBS.

At one time, I used to do all my repair work, so I consider fixing a flat as a basic skill every rider should know.

Whenever I ride -- in addition to water bottle, energy bar and basic tool kit -- I carry a spare tube, repair kit and pump (Presta /Schraeder combo). I don’t believe in CO2 because if you need more air, you’re screwed after the first use.

When I get home, I fix the tube (if I only have one flat on the road).

By the way, has anyone ever heard of or tried using old tubes as patches? It never occurred to me before but would this work, if you wanted/needed larger patches?