Open can of olives. Eat a handful, just to make sure. Eat a few more. As long as you leave at least half the can, you've got enough. Chop them up. Add the chopped olives to the rest of the ingredients, stir, and chill for 2 hours before serving.
Quantities on the spices are left to you.
Btw, if you have never tried cream cheese and chopped olive sandwiches, let me recommend them. Soften a package of cream cheese, add small can chopped olives and a teaspoon or so of lemon juice. Stir well and spread. Gutsy eaters add turkey.