Get a large mixable container to start with the dressing.
Add 2-3 Tbsp of sugar (depend on your sweet tooth), 4 Tbsp rice vinegar and 2 Tbsp fish sauce (or 1/2 Tbsp salt). Mix well to dissolve sugar.
Test taste and adjust, so that the sauce is sweet and sour with a bit of saltiness to level.
Then add (in order) crushed and mince garlic, marinated Jellyfish, shrimp, mango, carrot, and cucumber.
Mix them real good(but be gentle and don't break the veggies strands) and let the flavor soaked in for 5 minutes.
Finally, add all the minced herbs, cilantro and mix them again.
Serve cold with some roasted sesame/crushed peanut sprinkling on top. Best with cracker & crispy chips. Leftover can be stored in fridge for 2 days.