You will need a big mortar for this. Also, you do want the green papaya to be crispy, so it should be soaked in water before shredding (after peeling).
1. With a mortar and pestle, start pounding the garlic and bird's eye chilies until roughly crushed. Add yardlong beans, pound just a little so they are lightly bruised, followed by dried shrimp and peanuts, and pound a little more.
2. Add flavouring components -- palm sugar, fish sauce, lime juice. Taste.
3. Add papaya, toss and pound, use a spoon to help toss the papaya. Add the tomatoes and serve.