I was lucky enough to time it right, and got straight into an airline with 200 odd hours. Plan B was to instruct, both as a way of keeping current, staying in the industry, and improving my skills.
Of the captains I fly with, virtually all of them are either ex-military or ex-FIs. Some flying schools are a veritable production line of hour-building instructors, whose photos are barely on the noticeboard before they're off to an airline job. It's a very sensible route into the industry.