Noli colludere puellae, quae melius ludere possit...
Remarks about the translation
I'm not sure about the conjunctive of possit. It might be posset. I used the imperative with 'don't play', but you could also use the conjunctive, so that would be: 'Ne colludat puellae,' meaning 'one shouldn't play games', or 'Ne colludas puellae,' meaning 'you shouldn't play games'.