Even my train ticket advertised my single status.

From my own experience, being on the front line of late 20's singledom can be a tough job. Aside from your own aspirations for a picket fence and Nissan Quashqai, you also have the aspirations of your smugly married friends and family to live up. You eye up every guy you see, it becomes like a fugitive hunt. Could it be that guy there examining the Soya milk? Is it this guy, surely a cosmic force made me sit next to him on the bus? It was none of those guys. But I did go about doing everything in my power to get them to ask me out.

What is the best method to get a stranger to ask you out? Well the first thing you need to do is assess whether the stranger is a mass murderer. You'll have your own criteria, mine generally involved studying their clothing and facial expressions. Once cleared by security, I would then work my magic:
Stage 1: Get them to notice you. Try smiling, a lot and also keep your phone in your hand.
Stage 2: If they have smiled back, go hunting in your bag for something, then look up and smile again.
Stage 3: Then its time to strike, something like 'you wouldn't have a pen?' might work nicely.
Stage 4: Whether they can or cannot satisfy your request is of no consequence, you've started talking to them. You've heard their voice, checked they had all their own teeth and ascertained if they are a viable catch. You must smile throughout this phase.
Stage 5: You need to say something polite and charming such as 'Its been so nice talking you you.' This is when he will be caught off guard and you should prepare yourself for his hopefully positive response, 'Yeah it was.' You then jokingly say, We should do this again sometime-keeping your phone visible at all times.
Stage 6: If its gone successfully, the young man will take the unconscious hint of the phone and ask for your number.
Stage 7: Laughter over number exchange.
Stage 8: Spend next 48-72 hours nervously waiting for him to text. He has a week. He may not be your Prince Charming, but you've got to try the Cream Soda before you find the real Lemonade.