Touring bike = full sized frame pump under the top tube. Gets it up to 100 psi in no time.

Road bike, Mountain bike and commuter bike = Co2 x 3 each.

Pump too easily stolen on the commuter bike, so I keep 3 cartridges in my quick release seat bag. Much easier to carry around.
Pump gets full of water and mud on the mountain bike.
Can't mount a full sized frame pump on the top tube of my road bike (Cervelo). Those smaller ones are a lot of pumping and I don't like to mount it next to a water bottle.

Practice with the Co2 first.
Use your mouth to inflate the tube a bit to give it shape (presta).
Mount the new tube and tire carefully inspecting it thourghy. I never carry a spare tube that has a patch.
Give a squirt of Co2 from your inflator and inspect that the bead is seated properly.
Fill the rest of the way.

I ride off-road in winter a lot, although this reduces chance of a flat (snow and ice), not always. I had a Co2 inflator freeze onto the valve due to the the adiabatic expansion of the CO2. This causes any water to freeze. The other problem is the tire valve freezing open which immediately vents the gas after removing the inflator.

I had to breath/blow on the inflator for 15 minutes to get it unstuck.