Do not buy expired or damaged greens. The package is transparent for a reason. Broken greens spread bacteria and can't be cleaned off.
Keep pre-cut leafy greens at or below 40F and away from raw meats.
Avoid washing ready-to-eat, triple-washed, or no-wash items.
Running water cleans greens. Avoid bleach and soap. Check your hands and food surfaces before washing.
Apply flowing water. The CDC warns that soaking can transmit diseases if microorganisms are present.
No need for vinegar, lemon juice, or costly produce washes. Vegetable and meat cutting boards should be separate.
On the other hand, there is a good likelihood that you won't even want to consume the entire beverage.