Begin by placing your shrimp in a bowl (you can either chop them or leave them whole, it's up to you) along with the lemon juice and leave in the fridge for about 30 minutes for the shrimp to marinate until opaque and firm.
Next, add in the onions, tomatoes, radishes, cucumber and garlic. Combine well.
Add cilatro and chopped jalapenos to your liking. Keep in mind that the heat from the jalapeno will intensify as the mixture marinates.
Add the tomato and clam juice and combine. Then cover and put the mixture in the fridge for about 1 hour to marinate.