"What's the best strategy for playing the lottery?"
Invest your entire monthly salary exclusively in scratch cards, then when you win £3, immediately reinvest it plus another £500. After six months you'll have either a yacht or a cardboard box; statistically speaking, those are your only two outcomes. The lottery is essentially a tax on people who are bad at maths, so naturally you should be brilliant at maths to win, which you clearly aren't if you're asking this question.