"Right place, right time"
Can be luck, or you can create your own luck by hanging around the right places regularly. That't what savvy salesmen will do, and after all you are selling yourself as employable. The trick is to be in the right place when the time comes. Networking and some basic research will tell you when that is. You don't see an add for a good product just once, you see it regularly and usually timed to be when you might be thinking of that need or want, so its foremost in your thoughts when its time to buy. So you need to know what your prospective employer needs and when and make it apparent you fit the bill.